Novak Djokovic will not play at the Western and Southern Open after a "taxing" run that has brought him to the brink of a calendar Grand Slam.

The world number one's bid for a Golden Slam faltered at the Olympic Games as he lost to Alexander Zverev in the semi-finals in Tokyo.

Djokovic appeared to tire badly and finished fourth in both the men's singles event and the mixed doubles, opting out of the bronze medal match in the latter.

But victories at the Australian Open, French Open and Wimbledon mean 2021 is still on course to be the best year of Djokovic's career.

And the Serbian is taking a little time to prepare himself for the final push at Flushing Meadows, meaning no appearance in Cincinnati next week.

"Dear fans," he wrote on Twitter. "I wanted to share with you that I am taking a bit longer to recover and recuperate after quite a taxing journey from Australia to Tokyo.

"Sadly, that means I won’t be ready to compete in Cincinnati this year, so I'll turn my focus and attention to the US Open and spend some more time with family.

"See you in New York soon!"

Novak Djokovic led the ATP Tour's birthday message to Roger Federer, as the Swiss star celebrated his 40th on Sunday.

Federer, ranked ninth in the world, made his professional debut in 1998. He has gone on to win 20 grand slam titles, a feat matched by only Rafael Nadal and Djokovic, who tied his rivals with his triumph at Wimbledon in July.

His first grand slam title arrived at Wimbledon in 2003, when Federer was aged just 21. In 2004, 2006 and 2007, he won three out of the four majors on offer.

Federer has six Australian Open titles, eight Wimbledon triumphs, five US Open wins and one French Open success to his name, while he has also won six ATP Tour Finals.

Djokovic and Federer have met 50 times on the ATP circuit, with the Serbian shading their head-to-head record with 27 wins – their most recent encounter coming in the semi-finals of the 2020 Australian Open.

Yet it was he who led the tributes to a true great.

"Hey Roger, happy 40th birthday – 40th, wow, what a milestone! You still keep on inspiring and thriving on the court, off the court, inspiring all of us," Djokovic said in a video posted to the ATP Tour's official Twitter account.

"It's been a huge honour to share the tennis court and the tennis circuit with you in the last 15 years.

"Hopefully you can still keep on playing. The sport needs you, of course, and thanks for everything you have done and thanks for showing us that even at that age we can play at a very high level.

"All the best, I wish you health and love and happiness with your close ones and thanks again for everything."

Kei Nishikori, who has beaten Federer three times and suffered eight defeats to the Swiss, was next up.

"Roger, happy 40th birthday!" Nishikori said.

"You are still my idol, I always looked up to you and I hope we can play a couple more times and I hope you can still keep going and win grand slams."

World number 15 Felix Auger Aliassime shares his birthday with Federer, though the Canadian is some 19 years junior.

"Hey Roger, the big 40, while I'm just turning 21," he said. "It's amazing for the sport that I'm playing and you're still playing at the same time.

"I hope I'll still be playing when I'm 40 as well. Thank you for everything you've been doing for tennis, it's so good to still have you around, I hope you have a great birthday."

It was by no means certain the rescheduled Tokyo 2020 Olympics would even go ahead, such was the uncertainty caused by the coronavirus pandemic.

But go ahead they did and now here we stand on the eve of the closing ceremony in the Japanese capital.

They have certainly been a Games like no other and we all hope future Olympics will not be held under such unusual circumstances, and judging the success of Tokyo 2020 is no easy feat given the measures to do so are too arbitrary.

Having said that, here are the highs of the Games and some of the lows, too.

The highs…

WARHOLM AND MCLAUGHLIN HAMMER THE HURDLES

Karsten Warholm revelled in bringing the "wow" factor to the men's 400m hurdles, and rightly so. The Norwegian became the first man to break the 46-second barrier – running an astonishing 45.94 seconds to smash his own world record, five weeks after breaking a benchmark held by Kevin Young for 29 years. A day later, Sydney McLaughlin battered her own world record in the women's race, clocking in at 51.46s.

VAN VLEUTEN'S HEARTWARMING TRIUMPH

Five years ago in Rio, Annemiek van Vleuten was on course for victory in the women's cycling road race until a high-speed crash left her with minor fractures to her spine. To make matters worse, the Dutchwoman made headlines for celebrating what she thought was victory in the same event here in Tokyo – only to realise she had finished second behind runaway winner Anna Kiesenhofer. But finally, her golden moment arrived in the women's time trial – at the age of 38 years and 293 days, she became the third-oldest woman to win Olympic gold for the Netherlands.

SWIMMING STARS PROVE THERE'S LIFE AFTER PHELPS

Michael Phelps is an Olympics legend and no one can lay claim to more than the 23 golds or 28 overall medals he accrued over between 2004 and 2016. But a stellar cast this year proved swimming is in a very strong position. Emma McKeon took home seven medals (including four golds) – the joint-most of any woman at a single Games – while Ariarne Titmus' 200m and 400m free double was memorable, particularly her win over the great Katie Ledecky in the latter race. Caeleb Dressel took five golds to show his potential as Phelps' heir apparent, while Adam Peaty stunned again for Great Britain. It was some week in the pool.

THOMPSON-HERAH DOES THE DOUBLE-DOUBLE

Elaine Thompson-Herah announced herself to the world stage with a 100 and 200m sprint double at Rio 2016 but injuries in the intervening years stemmed her momentum a little. However, she peaked at the perfect time in Tokyo and backed up her double from Brazil – becoming the first woman to repeat on the 100 and 200m. Indeed, only Usain Bolt had ever previously done so.

THE AZZURRI'S GOLDEN HOUR

There was a shock in the men's 100m final where the unheralded Marcell Jacobs started the post-Bolt era with gold. That followed on from countryman Gianmarco Tamberi having minutes earlier shared high jump glory with Mutaz Essa Barshim. There were hugs aplenty as Italy, surely celebrating their greatest night at an Olympics, won two athletics golds at the same Games since Athens in 2004.

NEW EVENTS CATCH THE IMAGINATION

One of the most fascinating aspects of any Olympics is the new sports and categories that get added to the programme. At Tokyo 2020, skateboarding, surfing and climbing have all attracted new and younger audiences to the Games – while the addition of mixed triathlon and the mixed 4x400m track relay have been successes.

BILES' INSPIRATIONAL MESSAGE

On the one hand, the fact we saw so little of Simone Biles and some of the reprehensible bilge aimed her way over the decision to pull out of the women's team event after just one rotation and then miss four individual events can be seen as a negative. But, on the other hand, the fact that she came back to take bronze on the balance beam and use her platform to promote the importance of protecting mental health has to be seen as a high. It takes bravery and courage in her position to speak on such matters. Kudos to you, Simone.

And the lows…

EMPTY STADIUMS AN ENDURING IMAGE

Let's start with the obvious here and something that has been spoken about pretty relentlessly. The absence of fans has had a huge cost on the atmosphere at these Games. Magical moments and career peaks played out in front of huge, empty stadia has undoubtedly been a huge negative. Many will take the fact we got here and managed to hold a Games at all as a positive. And it is. But at times, the whole thing felt a bit… meh.

TENNIS' HEADLINE ACTS FAIL TO DELIVER

With so many of the top male players opting to skip Tokyo, there was a big focus on Novak Djokovic and the next checkmark on his quest for a rare Golden Slam (only Steffi Graf has ever done it). The Serbian fell short, dropping out at the semi-final stage then getting a little stroppy. Big things were also expected of Naomi Osaka – a home hope and the 'face of the Games'. She made it as far as round three before going down to Marketa Vondrousova.

THE TSIMANOUSKAYA SAGA

One of the ugliest stories to emerge from the Games was the story of Belarusian runner Krystsina Tsimanouskaya, who refused to board a flight after allegedly being taken to the airport against her will following her public criticism of her team's organisation on social media. Tsimanouskaya competed in only one event and claimed she was entered into a 4x400m relay despite never racing in the discipline, suggesting that was a result of members of the team being considered ineligible due to not completing enough doping tests. The Belarusian Sport Solidarity Foundation indicated Tsimanouskaya feared for her life upon returning to Minsk. The country is under the authoritarian leadership of president Alexander Lukashenko, whose son Viktor heads the national Olympic committee (NOC). Both men were banned last December from attending Tokyo 2020. The whole thing has been really rather unsavoury.

Jamaica completed a one-two-three clean sweep in the women's 100m sprint race in Tokyo, with gold medallist Elaine Thompson-Herah setting an Olympic record.

Thompson-Herah defended the title she won in Rio and became the second-fastest woman in history in the process, recording a time of 10.61 seconds.

Reigning world champion and compatriot Shelly-Ann Fraser-Pryce claimed silver, just .02 seconds ahead of Shericka Jackson as Jamaica completed a clean sweep which was celebrated on Twitter by Usain Bolt.

Legendary sprinter Bolt  – an eight-time gold medallist – retired in 2017, and the men's preliminary rounds struggled for big names in his absence.

Jamaica will have another chance of a medal in athletics, with 2019 world champion long jumper Tajay Gayle overcoming injury to make Monday's final with a leap of 8.14m.

Sweden sealed a one-two in the men's discus – Daniel Stahl taking gold and Simon Pettersson silver – while Poland won their second Olympic gold medal in a relay event in athletics, their mixed team succeeding in the same city in which their women had tasted victory in 1964.

NO LUCK FOR NOVAK

Djokovic's Golden Slam hopes were ended on Friday, and on Saturday, his medal hopes crumbled.

The world number one lost to Spain's Pablo Carreno Busta, who won 6-4 6-7 (6-8) 6-3 in the bronze medal match in the men's singles.

For Djokovic, it was a defeat which represented the end of his campaign.

He would have had another shot at bronze in the mixed doubles alongside Nina Stojanovic, but withdrew from that match, handing the medal to Ash Barty and John Peers of Australia in the process. 

"The exhaustion, both physical and mental, got to me and it's unfortunate that in the most important matches I just didn't deliver, but I gave it all," said Djokovic, whose attention will now turn to winning the US Open to complete a calendar Grand Slam.

BLACK FERNS RIGHT RIO WRONGS

New Zealand's women clinched gold in the rugby sevens on Saturday, overcoming France 26-12.

The Black Ferns cruised to the final in 2016, but slumped to a defeat to rivals Australia. Co-captain Portia Woodman was pictured in tears on the field in Brazil, yet her team made no such mistake this time around.

"Crying underneath the posts was one that I looked back on, but now it's gone," Woodman said. "Not when I look at this," she added, gesturing to the gold medal around her neck.

"Yeah, we've got titles and we've won things, but I want our group to be good people and show the world that you can be a good, genuine person and still have success," Woodman's fellow co-captain Sarah Hirini said. 

"Our programme allowed that. Things like this happen because you're able to be who you are."

In the bronze medal match, Fiji defeated Great Britain 21-12.

"We are totally gutted. We really thought we could come here and get a medal, but we just weren't good enough," conceded Team GB's Hannah Smith. "Fiji really brought it to us today, so fair play to them."

DEBUT BRONZE FOR WILSON, CHINA TAKE WINDSURFING GOLD

There was joy for Britain out on the water, however, as Emma Wilson – an Olympic debutant – won bronze in the women's windsurfing.

Wilson was already guaranteed a medal due to winning four races in the lead up to the final. The 22-year-old missed out on silver as Lu Yunxiu of China kept within a boat's length to claim the gold.

Charline Picon took silver to follow up her win in Rio five years ago.

"It's amazing. I tried so hard in that race - I just kept going and going," said Wilson. "I just want to win, but any medal is amazing. I'm super happy and I just gave it everything I had."

CHINESE TAIPEI WIN MAIDEN BADMINTON GOLD

Lee Yang and Wang Chi-Lin took home Chinese Taipei's first badminton gold on Saturday with a victory over Liu Yu Chen and Li Jun Hui of two-time reigning champions China in the men's doubles final.

Their victory brought up the seventh Olympic gold for Chinese Taipei – the previous six having been split across weightlifting (four) and taekwondo (two).

Malaysia claimed their first medal in Tokyo thanks to Wooi Yik Soh and Aaron Chia triumphing in the bronze medal match.

In total, Malaysia have claimed 12 medals in their Olympic history, but are yet to clinch gold in any event.

Novak Djokovic blamed mental and physical exhaustion after another desperate day for the Serbian at the Olympic Games meant he will leave Tokyo empty-handed.

The world number one lost 6-4 6-7 (6-8) 6-3 to Pablo Carreno Busta in the singles bronze medal match, smashing one racket against a net post and tossing another into the stands in gestures of frustration.

Djokovic then cited a shoulder injury as he pulled out of the mixed doubles third-place match. That decision meant Ash Barty and John Peers of Australia took bronze, with Djokovic and his unfortunate Serbia partner Nina Stojanovic finishing fourth.

"I am dealing with injuries. Not one, more than one," Djokovic said in an interview with Serbian media, according to tennismajors.com. "I hope that it won't stop me from going to the US Open, which is my next big goal.

"I feel bad for Nina because we did not fight for a medal in mixed, but my body said 'enough'. I have played under medications and abnormal pain and exhaustion."

The 34-year-old Djokovic said he had put his "very last source of energy" into the tournament and was satisfied with his effort, with a semi-final defeat to Alexander Zverev on Friday having left him resigned to a battle for what by his standards was perceived as a consolation prize.

But Djokovic added: "I know I've not played well today, and yesterday in the second and third set.

"The exhaustion, both physical and mental, got to me and it's unfortunate that in the most important matches I just didn't deliver, but I gave it all."

Djokovic suggested the Paris Olympics in 2024 were a possible target, although he must be becoming sick of Olympic tennis by now, having only one bronze to show for four attempts to win gold.

He took bronze in 2008 but lost to Argentina's Juan Martin del Potro both in the third-place match at London 2012 and the first round at Rio 2016.

Now there is more Games agony to digest, as well as a need to reboot ahead of the upcoming North American hardcourt swing and that US Open campaign. His hopes of a calendar Golden Slam are over but a sweep of the grand slams remains a possibility, having already landed the Australian Open, French Open and Wimbledon titles.

"I've had some heart-breaking losses at the Olympics Games," Djokovic said. "I know that those losses have usually made me stronger. I know that I will bounce back. I will try to keep going for the Paris Olympic Games. I will fight for my country to win medals."

Carreno Busta's reaction was thoroughly refreshing, with the Spaniard jubilant to secure a medal.

He said: "This week has been a very harsh week mentally for me. When I saw Novak lost, and I had to play him for this medal, I had my doubts.

"But last night I slept like I haven't slept in Tokyo. I slept for nine hours straight, that was an advantage to me. I came on to the court today knowing Spain was behind me.

"This is even more incredible than winning other tournaments. I've won Davis Cup, I've gone far in other tournaments, but winning an Olympic medal is indescribable. Words fail me, I felt Spain rallying behind me. A bronze medal is a dream come true for me."

The knock-on effort of Djokovic's withdrawal from the mixed doubles meant Barty and Peers added to Australia's medals haul without having to step on court for the third-place play-off.

Barty insisted she and Peers were worthy bronze medallists, saying: "It's incredible. It's unique circumstances and heartbreaking for Team Serbia not to get out on court.

"But for Johnny and I this is a dream come true for us. I feel like we've really deserved this one."

Novak Djokovic smashed one racket and threw another into the stands on the way to losing his bronze medal match at the Tokyo Olympics on Saturday.

Spain's Pablo Carreno Busta beat the world number one 6-4 6-7 (6-8) 6-3 to finish third in men's singles.

The shock result followed a day on from Djokovic's hopes of a Golden Slam being crushed by defeat to Alexander Zverev in the semi-finals.

In the wake of his singles third-place match setback, Djokovic also pulled out of the mixed doubles bronze match, citing a left shoulder injury.

Having already clinched the Australian Open, French Open and Wimbledon titles, Djokovic was eyeing gold at the Games before heading to the US Open in August, aiming to land the five biggest prizes in tennis in the same season.

That has never been achieved in a calendar year by a man, and Djokovic could not even manage a consolation prize from his singles mission in Japan. How serious his injury is now remains to be seen.

After levelling the singles match by taking the second-set tie-break, Djokovic boiled over in the first game of the decider, firstly when flinging his racket several rows back from the middle of the court after Carreno Busta put away a volley at the net.

Djokovic picked another racket from his bag but petulantly demolished that against a net post after dropping the third game to slide 3-0 behind, receiving a warning from the umpire for that violent outburst.

His anger may have been explained by injury or by his disappointment on Friday, when, as well as losing to Zverev, Djokovic and Serbian team-mate Nina Stojanovic were beaten in the semi-finals of the mixed doubles.

Djokovic would have had one final shot at a medal from his Tokyo trip to come later on Saturday, with the 34-year-old and Stojanovic due to face Ash Barty and John Peers in another match for bronze.

However, shortly after his singles exit, it was announced that Djokovic had pulled out of that match, handing Barty and Peers the medal.

Amid the anger and frustration exhibited on court by Djokovic, it was a banner day for Carreno Busta, as Spain celebrated another tennis medal, having won at least one in eight of the last nine Olympics.

The 30-year-old fell to the court in joy at the end of the two hours and 47 minutes it took him to defeat the world number one, his elation a sharp contrast to the emotions of his beaten opponent.

World number one Novak Djokovic is desperate to rebound after his men's singles semi-final defeat, targeting "at least one medal" for Serbia with two bronze medal matches on Saturday.

Djokovic, chasing an elusive Golden Grand Slam, went down in three sets to German fourth seed Alexander Zverev on Friday in the men's singles.

The Serbian will instead face Pablo Carreno Busta in the men's singles bronze medal match on Saturday, while he has another medal hope in the mixed doubles.

Djokovic has partnered with Nina Stojanovic and will face Australian duo Ashleigh Barty and John Peers in the bronze medal match also on Saturday.

“I feel terrible right now in every sense but tomorrow hopefully a fresh start I can recover and win at least one medal for my country,” Djokovic said.

After losing to Zverev 1-6 6-3 6-1, Djokovic's tough day was compounded with defeat alongside Stojanovic in the mixed doubles' semi-finals to the Russian Olympic Committee's Elena Vesnina and Aslan Karatsev 7-6 (7-4) 7-5.

“Tough day, a really tough day," Djokovic said. "I feel so terrible right now. I was leading by a set then a break and [Zverev] managed to turn the match around.

"He served huge, was attacking, and I was not getting any free points on my first serves.

“I've got to give him credit for turning the match around. He served extremely well. I mean I was not getting too many looks on the second serve.

"My serve just drastically dropped. I didn’t get any free points from 3-2 up in the second. My game fell apart.

“To play someone of his quality, of his level, it's just too tough to win a match [like that]. It’s just sport. He played better.”

Selemon Barega took the first athletics gold of the Tokyo 2020 Olympics on a day when Novak Djokovic saw his Golden Slam hopes ended.

Barega topped the podium for Ethiopia as he saw off competition from Ugandan duo Joshua Cheptegei and Jacob Kiplimo on Friday.

The 21-year-old ran a smart race and had the stronger finish in him to see off pre-race favourite Cheptegei, who took silver ahead of compatriot Kiplimo.

"It means a lot to me because I have been practising a lot, not only by myself but together with the Ethiopian people," said Barega, who quickly sets his sights on future success.

"As an athlete the primary target for us is to participate in the Olympics, be a champion, and also be able to break the record.

"So I'm really thinking about future opportunities for me to achieve that, and if possible I'm also communicating with my manager about that."

There was no such joy for Djokovic as his bid to become the first man to win a calendar Golden Slam was crushed by a semi-final defeat to Alexander Zverev.

Djokovic was a set and a break up but the Serbian contrived to lose eight games in a row en route to a 1-6 6-3 6-1 loss.

Germany's Zverev had sympathy for his beaten opponent, who he declared as the greatest of all time.

He said: "I know that he was chasing history, chasing the Golden Slam and chasing the Olympics, but in these kind of moments me and Novak are very close. Of course I'm happy that I've won, but at the end of the day I know how Novak feels.

"I feel sorry for Novak, but he's won 20 grand slams, 550 Masters Series or whatever, you can't have everything.

"He's the greatest player of all time, he will win the most grand slams out of anybody on tour, but I'm also happy that I'm in the final."

Defeat in the mixed doubles means the 20-time grand slam champion will face two bronze medal matches in Japan.

MIXED RELAY WOES FOR USA

The 4x400 metre relay mixed event made its debut in the Olympics on Friday but it did not go well for the favourites as the United States suffered disqualification.

One of the team's baton exchanges was deemed to have taken place outside the designated zone, ending their campaign and leaving the gold medal up for grabs.

Poland qualified fastest with a time of three minutes 10.44 seconds, with the Netherlands close behind and Jamaica also in the mix.

SCHAUFFELE LEADS THE WAY IN RAIN-AFFECTED MEN'S GOLF

Xander Schauffele fired a 63 to move top of the leaderboard at Tokyo 2020, while home favourite Hideki Matsuyama and Rory McIlroy made big moves on Friday.

The threat of serious weather caused another delay on day two, and eventually brought an early end to play with Matsuyama among those not to finish his round.

But Schauffele, who has a big following in Japan as his mother was brought up in the country, sat pretty at 11 under as the stellar names bared their teeth at Kasumigaseki Country Club.

Matsuyama was six under through 16 holes of his second round and eight under overall for the tournament.

McIlroy matched Matsuyama's round-one score but shot five under in round two and is well in the mix four shots back.

A LONG TIME COMING

Ma Long took gold in the table tennis as he became the first man to win consecutive Olympics titles in the event.

It was an all-Chinese final and Ma roared to victory against Fan Zhendong.

China also secured a one-two in the badminton mixed doubles.

IGLESIAS CAN BE CUBA'S HERO

Cuban welterweight fighter Roniel Iglesias earned a third Olympic medal after sinking American Delante Johnson with a sweep of the scorecards.

After a bronze in Beijing and gold at London in 2012, Iglesias savoured another chance to target the top step of the podium.

The 32-year-old said: "It is my third medal which is very important but what I really want is to win the gold medal. It is a historic moment for me and for my country, Cuba. I am very happy at this achievement."

Light heavyweight Ben Whittaker admitted he was a blubbering mess after securing at least a bronze medal for Great Britain. He set up a semi-final against Imam Khataev – representing the Russian Olympic Committee – after scoring a majority points win over Brazilian Keno Machado.

Whittaker was overwhelmed by the result and burst into tears at the realisation he would be taking home a medal.

"That was the hard part, getting that medal," Whittaker said. "I won't relax, but I've pushed through that first door now and all I have to do is start changing that colour. Bronze is a lovely colour but everyone wants gold."

DRAMA APLENTY IN WOMEN'S FOOTBALL

The quarter-finals of the women's football competition delivered on drama in a big way.

Penalty shoot-outs were needed for Canada and the United States to progress to a last-four showdown, with Brazil and the Netherlands their respective victims.

Australia won a seven-goal thriller 4-3 against Great Britain after extra time and will now meet Sweden, who knocked out hosts Japan 3-1.

Alexander Zverev apologised to Novak Djokovic after ending the Serbian superstar's hopes of a glorious Golden Slam – but joked it was about time someone else landed a major tennis title.

In their Olympic Games semi-final, it seemed Djokovic was cruising through to the gold medal match when he surged a set and a break of serve ahead.

Incredibly, though, Zverev won 10 of 11 games from 3-2 behind in the second set to take the match 1-6 6-3 6-1 and set up a shot at Karen Khachanov in Sunday's final.

Djokovic swept to Australian Open, French Open and Wimbledon trophy success before heading to Japan for the Olympics, the fourth leg of a potential sweep of each of the year's majors and the Tokyo 2020 singles title.

He had spoken of it becoming closer to a reality, as he attempted to match Steffi Graf's achievement from 1988, when she followed triumphs at each of the slams by winning in the October 1 final at the Olympics, held in Seoul that year. Graf remains the only player to have pulled off the feat in the same year.

Zverev had other ideas, but he also had sympathy for Djokovic when they exchanged words at the net.

"I told him that he's the greatest of all time, and he will be," Zverev said.

"I know that he was chasing history, chasing the Golden Slam and chasing the Olympics, but in these kind of moments me and Novak are very close. Of course I'm happy that I've won, but at the end of the day I know how Novak feels.

"I feel sorry for Novak, but he's won 20 grand slams, 550 Masters Series or whatever, you can't have everything.

"He's the greatest player of all time, he will win the most grand slams out of anybody on tour, but I'm also happy that I'm in the final."

Victory at Wimbledon earlier in July took 34-year-old Djokovic to 20 grand slam titles, level with Roger Federer and Rafael Nadal for the most by a man in the history of tennis, and Zverev was lurching towards becoming his latest victim when their Tokyo tussle began in a one-sided manner.

"I was down a set and a break, so I needed to change something. I started playing much more aggressive," Zverev said. "I started to swing through the ball a little bit more, and I tried to dominate that way."

Zverev is assured of at least a silver medal now, while Djokovic faces a bronze medal play-off against Spain's Pablo Carreno Busta.

"It's an amazing feeling knowing that you're going to bring the medal back to your house, back home to Germany," Zverev said.

"It's incredible beating the best player in the world undoubtedly right now and in this season. It seemed it was impossible to beat him at this event, so I’m very happy right now. But yet there's still one match to go."

Novak Djokovic's hopes of becoming the first man to win a calendar Golden Slam were crushed by a semi-final defeat to Alexander Zverev at the Tokyo Olympics.

From a set and a break up, Djokovic dropped a staggering eight games in a row on his way to a 1-6 6-3 6-1 loss.

The 34-year-old Serbian had been unsure about coming to the Games but was swayed by the pride he takes in representing his country and the tantalising opportunity to add a gold medal to a potential clean sweep of the grand slams.

He has already won the Australian Open, French Open and Wimbledon, and will head to the US Open in August as a heavy favourite regardless of this setback.

But this was just not Djokovic's day, despite him making a whirlwind start and dominating until the point he broke to lead 3-2 in the second set. From there, Zverev seized control. 

When Djokovic volleyed into the net to make it 3-3, dropping serve for the first time in the match, it looked like just a minor stumble.

Yet suddenly he was struggling for form and did not win another game until he was already 4-0 behind in the deciding set.

Zverev was playing blindingly brilliant tennis and was proving obdurate too, saving four break points in the second game of the third set.

He clinched victory with a blazing backhand winner, and goes on to face Russian Karen Khachanov in the final.

The result means Djokovic, like Roger Federer, seems fated never to win the Olympic singles gold medal. And it leaves Steffi Graf as the only player to ever win a calendar Golden Slam, having done so in 1988 when she added the Seoul Olympics title to her haul of majors.

Russian Olympic Committee's Khachanov fended off Spain's Pablo Carreno Busta with some ease in the first semi-final, with the world number 25 sweeping to a 6-3 6-3 victory in an hour and 19 minutes.

He won 26 of 28 points on first serve to freeze out Carreno Busta, who had only one break point all match and could not take that opportunity.

"It's just a pure happiness, a pleasure to be here to live those moments, these kind of memories will stay forever," Khachanov said.

Khachanov delivered a rock solid display, with his serve and forehand at their best, barely giving his opponent a sniff of an opportunity as the Moscow-born 25-year-old established a firm grip.

"That's the way I prepared, against every opponent you play a little bit differently," Khachanov said. "The final will be another story, another match, another day. I hope it will be the same."

Carreno Busta, who will face Djokovic for the bronze medal, said: "It was not the best match I have played, but Karen was unbelievable today, playing very aggressive and serving really good."

Friday sees the start of the Olympic athletics schedule and the first tennis medals will be won in Tokyo.

The men's 10,000 metres final will be staged on the first day of track and field action at the Olympic Stadium.

There will be an all-Croatia men's doubles gold medal match at the Ariake Tennis Park, plus no doubt more drama to come in the pool.

Stats Perform picks out some of the standout events to look forward to.

CHEPTEGEI FAVOURITE FOR FIRST TRACK GOLD

Joshua Cheptegei and Jacob Kiplimo both have the chance to become the first athlete from Uganda to win an Olympic gold medal in the men's 10,000m final.

Cheptegei, the 2019 world champion, is well fancied in the last event on the track on Friday, while his compatriot Kiplimo could become the youngest man to be crowned champion at the distance at the age of 20 years and 258 days.

Yomif Kejelcha of Ethiopia and Canadian Mohammed Ahmed also have high hopes of making it onto the podium. 

Other events to look out for are the start of the women's 100m, men's 400m hurdles and men's high jump, along with the women's 800m and women's triple jump.

CROATIA GUARANTEED DOUBLES GOLD

One guarantee on Friday is that Croatia will add a gold and silver medal to their tally at the Tokyo Games.

Marin Cilic and Ivan Dodig will face compatriots Nikola Mektic and Mate Pavic in the gold medal match in the men's doubles final.

The men's singles semi-finals will also take place, with Novak Djokovic, chasing a Golden Slam this year, up against Germany's Alexander Zverev.

Karen Khachanov of the Russian Olympic Committee will do battle with Spaniard Pablo Carreno Busta to find out who will make it through from the other half of the draw.

HIGH HOPES FOR AUSTRALIAN DUO

Emma McKeon and Cate Campbell could make it an Australia one-two in the women's 100m freestyle final.

McKeon set a new Olympic record of 52.13 seconds on Wednesday and will go out in lane four next to her dangerous compatriot Campbell.

That is one of four finals on Friday, with Tatjana Schoenmaker of South Africa expected to take some stopping in the 200m breaststroke final after clocking an Olympic record time of 2:19.16 this week.

Medals will also be up for grabs in the men's 200m backstroke final and the men's 200m individual medley.

Sunisa Lee stepped up in the absence of Simone Biles to claim gold and maintain Team USA’s dominance in the women's gymnastics all-around event.

The 18-year-old became the sixth American woman to take the title – and fifth in a row – after beating Brazil's Rebeca Andrade and Angelina Melnikova to gold.

Despite withdrawing from the final to focus on her mental health, Biles was cheering on from the stands as her team-mate aimed to capitalise.

Lee was looking to continue her nation's impressive record in this event, which has seen triumph concurrently at both the Olympic Games and World Championships since 2010.

The teenager admitted she came close to quitting gymnastics following a difficult two years – both in and out of the gym.

Nevertheless, she duly delivered the goods by totalling 57.433 to take gold and edge out Andrade, who became the first Brazilian woman to claim an Olympic medal in artistic gymnastics.

"It feels crazy, it is so surreal. It's a dream come true," Lee said. "I don't even know what to say. It hasn't even sunk in. The past two years with COVID have been crazy. There was one point I wanted to quit. 

"To be here and to be an Olympic gold medallist is just crazy."

PATIENT FOX COMES GOOD

Australia's Jess Fox became the first women's canoe slalom (C1) Olympic gold medallist.

A multiple World champion, Olympic gold has eluded Fox over the years. She was a silver medallist at London in 2012, while she took home a bronze from Rio four years later.

However, her persistence finally paid off after posting a time of 105.04 seconds in the final, while Great Britain's Mallory Franklin and Andrea Herzog of Germany completed the podium.

"I can't believe it," said Fox, who also won bronze in the women's kayak earlier this week.

"I was dreaming of [a gold medal] and I really believed it was within me, but you never know what is going to happen at the Olympics.

"It is about holding your nerve and I probably didn't do that very well in the kayak a couple of days before, so it was hard to get to this point. But it has been incredible to do what I did today."

Novak Djokovic is growing in confidence after his bid to win a gold medal at the Olympic Games stayed on track on his "best day" of Tokyo 2020.

The Serbian cruised into the semi-finals of the singles tournament with an emphatic 6-2 6-0 win over home favourite Kei Nishikori of Japan, then teamed up with Nina Stojanovic to beat German pair Laura Siegemund and Kevin Krawietz in the mixed doubles quarter-finals.

World number one Djokovic, 34, is attempting to become the first man to win all four tennis singles grand slam titles and an Olympic gold in the same year.

He has already triumphed at the Australian Open, French Open and Wimbledon, leaving just Tokyo and the US Open to conquer.

Asked after his doubles win if this was the best year of his career, Djokovic replied: "I don't know. Today was the best day of this tournament because I've played my best tennis so far."

Those comments echoed his assessment of the Nishikori match, after which he said: "I'm very happy – my best performance in the tournament."

Djokovic said he "had an answer for everything [Nishikori] had" and now he will face Alexander Zverev.

Asked how confident he felt heading into the last four, the 20-time grand slam champion replied: "Very."

Djokovic was boosted by the later start times for his matches after the International Tennis Federation bowed to pressure from players complaining of the extreme heat and humidity at Ariake Tennis Park.

"It's great that we're playing in the afternoon hours, so we don't experience too much heat," Djokovic said.

"Although it's still very, very humid. It's a bit easier, more pleasant to play in the afternoon. It was fantastic. 

"Playing after 5[pm] is completely different.  Obviously, there is a little bit of a breeze, but still very, very humid, you sweat a lot, but you don't have the heat, you don't have the sun that, in combination with the humidity, is just brutal."

Novak Djokovic cruised through to the men's singles semi-finals after a commanding straight-sets victory over Kei Nishikori at the Ariake Tennis Park.

The world number one is yet to drop a set at the Tokyo Games after running out a 6-2 6-0 winner against home favourite Nishikori, who claimed bronze in Rio five years ago.

Having already won the Australian Open, French Open and Wimbledon this year, Djokovic is aiming to become the first male player of the Open era to complete the Golden Grand Slam.

Should he claim gold in Tokyo and go on to triumph at the US Open, he would become only the second player overall to achieve the feat, after Steffi Graf in 1988.

However, the Serbian has never reached an Olympic final – his best result coming in for the form of a bronze medal in Beijing.

"Matches are not getting easier, but my level of tennis is getting better and better," Djokovic told reporters after setting up a last-four tie with Alexander Zverev.

"I've done that many, many times in my career. I know that I'm the kind of player that the further the tournament goes, the better I'm feeling on the court.

"That's the case here, [it was] my best performance of the tournament tonight against a very good opponent."

DANIIL DUMPED OUT

Standing in the way of Djokovic and a shot at the gold medal is fourth seed Zverev.

The big-serving German saw off Jeremy Chardy 6-4 6-1 and like Djokovic is yet to drop a set at the tournament.

World number five Zverev, who hit 11 aces during the contest, broke early on the way to edging a closely fought opening set. The US Open finalist then went into overdrive with three breaks on the way to sealing the deal.

There was, however, no joy for second seed Daniil Medvedev, as he went down 2-6 6-7 (5-7) against Spain's Pablo Carreno Busta, who is looking to replicated Rafael Nadal's effort from 2008.

"Today, he could win a Masters easily, and yet he's never been in any final of those," the Russian said of his opponent.

"With the level he showed here today, he can get to the final of a Grand Slam easily. I couldn't play better than what I did today. It was not easy to play and I'm really disappointed with myself and for my country to lose in the quarters."

FROM RUSSIA WITH LOVE

Despite Medvedev's exit, Russia – or, at least, the Russian Olympic Committee – will be represented in the semi-finals by Karen Khachanov.

A quarter-finalist at Wimbledon earlier this month, the 12th seed built on his momentum by overcoming Ugo Humbert in three sets.

Khachanov took the opener on a tie-break but was pegged back by the Frenchman in the second as the contest went to a decider.

But he established early control by breaking to love in game four before holding out to prevail 7-6 (7-4) 4-6 6-3.