Andrey Rublev produced a stirring fightback to defeat Stefanos Tsitsipas and reach the last four of the ATP Finals for the first time on Friday.

Rublev had failed to make it out of the group stage on each of his first two appearances at the season-ending showpiece.

It initially looked as if he would fall short once again in this winner-take-all clash with Tsitsipas, with both men looking to join Novak Djokovic in progressing from the Red Group.

He was outclassed by Tsitsipas in the first set but showed the grit to recover from 0-30 down in the opening game of the second to find a crucial hold of serve.

That proved the catalyst for a stunning turnaround, as Rublev dominated with his fierce forehand and a series of superb passing shots to seal a 3-6 6-3 6-2 victory in Turin.

He will face Casper Ruud on Saturday for a place in the final.

Rublev told Prime Video of that semi-final encounter: "I'm really looking forward because Casper is such a nice person, great player, great fighter, he has achieved so many things this season, so it's going to be a really good challenge for me."

ACES/DOUBLE FAULTS

Rublev – 10/2
Tsitsipas – 10/2

WINNERS/UNFORCED ERRORS

Rublev – 36/22
Tsitsipas – 25/12

BREAK POINTS WON

Rublev – 3/5
Tsitsipas – 1/3

Stefanos Tsitsipas saw off an impressive Daniil Medvedev comeback bid to keep his ATP Finals last four hopes alive with a 6-3 6-7 (11-13) 7-6 (7-1) win in Turin.

With both men having lost their opening match in their first red group encounters, the two headed into their Wednesday match knowing they needed a victory to stay in the semi-final hunt.

Now, it will be 2019 Finals winner Tsitsipas who remains in the mix after seeing off 2020 champion and former US Open winner Medvedev across a two-hour-and-21-minute encounter, handing Novak Djokovic the group in the process.

The Greek second seed looked to be racing away to an early finish after cruising to the first set, but found himself embroiled in a much closer follow-up.

A bruising second set forced the pair into a lengthy tie-break, which stretched its points out to double figures before Medvedev prevailed.

The two could then not be separated in the third, only for Tsitsipas to dominate the tie-break the second time around and race away to a crucial win that sets up a winner-takes-all clash with Andrey Rublev.

ACES/DOUBLE FAULTS

Tsitsipas – 9/1
Medvedev – 16/2

WINNERS/UNFORCED ERRORS

Tsitsipas – 47/25
Medvedev – 34/28

BREAK POINTS WON

Tsitsipas – 2/3
Medvedev – 1/1

In recent years, the notable absentee at the ATP Finals has been Roger Federer, with his last appearance in the tournament coming in 2019.

The lack of Federer at the showpiece event will be felt even more apparent this year after the Swiss maestro retired from tennis in September, though it is the absence of a player at the other end of his career that is more relevant in Turin.

World number one Carlos Alcaraz had to withdraw from the tournament after suffering an abdominal tear, which means his status at the top of the men's game is in jeopardy.

Rafael Nadal has spoken well of his 19-year-old compatriot in the past, but is not ready to pass the torch just yet, and could even topple Alcaraz from his number one spot.

The 22-time grand slam champion has finished as year-end number one five times previously, most recently in 2019. Should he accomplish the feat again this year it would put him in joint-second for most year-end finishes at the top of the ATP Rankings (since 1973) along with Pete Sampras (six).

In order to do so, Nadal will need to win the tournament, something he has never done before.

However, he comes into his 11th appearance in good form, and has won 32 per cent of his return games in 2022, the highest percentage by any player this year, and has converted 43.8 per cent of his break points in 2022, the third best amongst all players.

Stefanos Tsitsipas, meanwhile, is the other competitor who can knock Alcaraz off top spot, though his task to do so is a little more complicated as he needs to win every match on the way to the title in Turin. 

No player has played more matches in 2022 than Tsitsipas (80), 21 on clay, 11 on grass and 48 on hard courts; he has won 59 of them and lost 21.

Should neither man win at the Pala Alpitour, Alcaraz will breathe a sigh of relief and earn his first year-end number one finish, having taken his place after winning the US Open in September.

Nadal has been drawn into the Green Group with Casper Ruud, Felix Auger-Aliassime and Taylor Fritz, while Tsitsipas will be in the Red Group alongside Daniil Medvedev, Andrey Rublev and Novak Djokovic.

Djokovic can equal Federer record

One man surprisingly unable to end the year as number one is Djokovic, despite having done so on more occasions than anyone else in history (seven).

However, the 21-time grand slam champion can still make his mark in Italy.

Djokovic has had an up-and-down year, only playing in two of the four grand slams due to his vaccination status, though he was able to win Wimbledon for the seventh time, beating Nick Kyrgios in the final.

Should the Serbian go all the way and lift what would be his sixth ATP Finals title, he will go level with Federer for most victories since the tournament began in 1970.

Among the eight participating players in this year's tournament, Djokovic has won 87 per cent of his service games in 2022, the best percentage among these players and the sixth overall.

It would be quite the ending to the year for Djokovic, who finds himself in the unusual position of sitting eighth in the world rankings, and at the age of 35, who knows how many more appearances he will make at the event?

Strong field promises fireworks

As is the intent of the format, the ATP Finals should be a tightly-contested few days as the best men's players in the world come together.

Ruud will be looking to add to an already impressive season, having reached two grand slam finals and winning three tour-level titles, while Fritz is aiming to carry on the fine lineage of American players to have won the tournament.

Players from the United States have won the ATP finals 16 times, with Sampras and Ivan Lendl winning five of them each. It is the most by any country and 10 more than next best Switzerland (six, all Federer) and Germany (also six, three wins for Boris Becker, one for Michael Stich and two for last year's champion, Alexander Zverev).

Auger-Aliassime has had a strong end to the year, beating Djokovic at the Laver Cup before winning three titles in as many weeks in Florence, Antwerp and Basel.

Only John Isner (895) has recorded more aces in 2022 than Auger-Aliassime, who has registered 852 in total, averaging 10.9 per match.

"All the players who participate [at the ATP Finals], I have already faced them, I have beaten them," the Canadian recently said. "So for me, there's no reason why I can't show up to this tournament with the aim of winning it."

Medvedev was world number one as recently as September but enters this tournament in fifth, though he did win the Vienna ATP 500 event last month, while his first opponent in Turin, Rublev, enters with a 2022 record of 49-18, looking for his second straight 50-win season.

Whoever comes out on top at this year's ATP Finals, the race for supremacy in 2023 promises to be as delightfully chaotic.

Novak Djokovic overcame Stefanos Tsitsipas in a dramatic final-set tie-break to reach the Paris Masters final on Saturday, teeing up a meeting with Holger Rune. 

Djokovic's 12-match winning run looked likely to be halted when Tsitsipas found a mini-break in the decider, with the Greek having fought his way into contention after losing the opening set.

However, the 21-time grand slam champion stepped up when it mattered, winning the final four points of the match to seal a 6-2 3-6 7-6 (7-4) victory.

The Serbian, who will now take part in his record 56th Masters 1000 final on Sunday, opted to praise Tsitsipas for his role in a thrilling encounter following the win. 

"It's very sweet, obviously, when you win matches like this against one of the best players in the world," Djokovic said.

"I thought I started the match very well, again, great hitting, like yesterday in the quarters. I had chances early on in the second, I didn't break his serve. The momentum shifted, the crowd got into it. I think he elevated his level of tennis.

"We went into an even battle all the way until the last point, until the last shot. Some incredible points towards the end. I'm just really glad to overcome this challenge."

In Saturday's other match, Rune clinched his first Masters 1000 final appearance by posting a straight-sets victory over Felix Auger-Aliassime.

The in-form Dane seized control of the contest after breaking in the third game of the opener, and did not give up a single break point en route to a comprehensive 6-4 6-2 win.

In doing so, Rune exacted revenge for last week's defeat to Auger-Aliassime in the Swiss Indoors final in Basel, halting the Canadian's 16-match winning run.

Rune has now won eight career matches against top-10 opponents, and half of those victories (four) have come during his strong run in Paris this week.

Novak Djokovic remained on course for a record-extending seventh Paris Masters title after booking his quarter-final place with victory over Karen Khachanov.

The six-time champion avenged his defeat by Khachanov in the 2018 Championship match by running out a commanding 6-4 6-1 winner.

That gave Djokovic his 11th straight victory in the French capital, where he is unbeaten since that 2018 defeat, while he has also won each of his last 11 Tour-level matches.

The Serbian, who has triumphed in Tel Aviv and Astana during that streak, set up a last-eight clash with Lorenzo Musetti after the Italian came from behind to stun third seed Casper Ruud 4-6 6-4 6-4.

The Naples champion recorded his maiden top-five victory at the seventh attempt, while he hit 37 winners to advance to his first ATP Masters 1000 quarter-final.

Meanwhile, world number one Carlos Alcaraz won five out of seven break points as he breezed past Grigor Dimitrov 6-1 6-3 to reach the last eight in Paris for the first time.

There, he will play Holger Rune after the Stockholm champion defeated seventh seed Andrey Rublev in straight sets.

Fifth seed Stefanos Tsitsipas overcame Corentin Moutet 6-3 7-6 (7-3) to reach his 14th quarter-final of the season, where he will face Tommy Paul after the American denied Pablo Carreno Busta 6-4 6-4.

Felix Auger-Aliassime was a commanding 6-1 6-3 victor over Gilles Simon. The eighth seed will take on Frances Tiafoe, who defeated Alex De Minaur 6-3 7-6 (7-5).

Stefanos Tsitsipas crashed out of the Vienna Open after losing in a dramatic third-set tie-break against Borna Coric, who claimed his third successive win over the Greek ace.

The second seed was the highest-profile casualty in the Austrian capital on Thursday, as he succumbed to the Croatian once more 4-6 6-4 7-6 (7-4).

Coric rescued six match points before stunning Tsitsipas at the 2020 US Open, while he also triumphed when they collided in the Cincinnati showpiece in August.

The world number 27's chances of completing a hat-trick of victories appeared bleak at a set and break down, but he rallied to force a decider that went the distance, before holding his nerve for another notable win.

Coric's reward is a quarter-final clash with Hubert Hurkacz, who boosted his chances of qualifying for next month's ATP Finals with a 7-5 4-6 6-3 win over Emil Ruusuvuori.

Daniil Medvedev advanced to the last eight after a 6-3 6-3 victory over home favourite Dominic Thiem. Next up for the top seed is Jannik Sinner after the Italian saw off Francisco Cerundolo 7-5 6-3.

Third seed Andrey Rublev's ATP Finals hopes were dented after a 6-3 6-4 defeat by Grigor Dimitrov, who will play Marcos Giron after the American overcame seventh seed Cameron Norrie in straight sets.

Over in Basel, third seed Felix Auger-Aliassime required just 49 minutes to complete a commanding 6-1 6-0 rout of Miomir Kecmanovic for his 10th straight ATP win.

Meanwhile, Stockholm champion Holger Rune continued his momentum by recording a seventh straight victory after seeing off Ugo Humbert 6-4 6-2.

Sixth seed Roberto Bautista Agut enjoyed a straight-sets win over three-time grand slam champion Andy Murray to set up a clash with home favourite Stan Wawrinka, who outlasted Brandon Nakashima in a deciding set.

Daniil Medvedev set up a second-round showdown with home favourite Dominic Thiem at the Vienna Open after defeating Nikoloz Basilashvili in straight sets on Wednesday.

The top seed broke early and late in both sets as he cruised through the opening round a 6-2 6-2 winner.

Next up for Medvedev is a clash with former US Open champion Thiem, who beat him in the semi-finals on the way to triumphing at Flushing Meadows two years ago.

Stefanos Tsitsipas overcame local wildcard Dennis Novak 7-6 (7-2) 6-2 as the Greek ace seeks a third final in as many weeks, having lifted the title in Astana and finished as runner-up to Holger Rune in Stockholm.

Jannik Sinner also advanced in straight sets against Cristian Garin, but Taylor Fritz's ATP Finals hopes suffered a blow after the fourth seed was beaten 6-1 4-6 6-3 by Denis Shapovalov.

Over in Basel, world number one Carlos Alcaraz sailed through to his 11th quarter-final of the season after a commanding 6-4 6-2 win over Botic van de Zandschulp.

Meanwhile, Felix Auger-Aliassime recovered from losing the opening set to deny Marc-Andrea Huesler. The third seed claimed a career-best ninth successive ATP Tour victory, as he looks to complete a hat-trick of titles in as many weeks having recently reigned in Florence and Antwerp.

Stockholm champion Rune built on his recent momentum with a 6-2 7-5 success over Alex de Minaur, but Naples winner Lorenzo Musetti was ousted in a deciding set by Albert Ramos-Vinolas. 

Holger Rune surprised top seed Stefanos Tsitsipas with a straight-sets victory in Sunday's Stockholm Open final to land his second ATP title.

Still just 19, Rune added to his maiden crown in Munich five months ago with a 6-4 6-4 triumph over world number five Tsitsipas in a match lasting 95 minutes.

Tsitsipas, who was seeking a 10th ATP title and a third this season, had not dropped a set in his previous three matches en route to the final.

However, he was broken in the third game of both sets against Rune, who is the second teenager after Carlos Alcaraz to win multiple ATP titles in 2022.

Rune fired 20 winners and saved the only break point he faced – that coming in the sixth game of the second set – on his way to becoming the first Danish champion in this event.

"It was an unbelievable match from my side," Rune said in his on-court interview. "I knew it was going to be difficult, but I just tried to stick to the game plan. 

"I had to play my best tennis today, and it was good that I could find the level. I am super happy. It was very close to perfection. 

"I was making a lot of returns and playing pretty well behind my serve. Stefanos is an amazing player, who always makes it difficult. It was a super fun match to play."

Matteo Berrettini is set to tackle Davis Cup team-mate Lorenzo Musetti in an all-Italian Napoli Cup final on Sunday after defying advice to pull out with a foot injury.

Former Wimbledon runner-up Berrettini beat American Mackenzie McDonald 3-6 7-6 (7-2) 6-3 at the hard court event, while Musetti came through 6-3 6-4 against Serbian Miomir Kecmanovic.

Providing Berrettini is healthy to participate in the final, the tournament looks set to deliver a crowd-pleasing trophy match, but it was touch and go whether the Rome native would get through the McDonald match.

"I don't even know how I did it," Berrettini said. "I wasn't feeling very good. I asked for the physio because my foot was hurting. It happened so many times in my career that I had to fight through so many things, not just thinking about the tennis ball."

He added, quoted by the ATP: "I didn't want to retire. My team told me, 'I think you should stop'. But I tried and I found a way."

Berrettini and Musetti have never gone head-to-head before. Berrettini has won two titles this year, both on grass, in Stuttgart and at London's Queen's Club, while 20-year-old Musetti scooped his maiden ATP title on clay in Hamburg.

At the European Open in Antwerp, Sunday's final will see American Sebastian Korda tackle Canadian Felix Auger-Aliassime, in a battle of two in-form players.

Korda was runner-up last week in Gijon, while Auger-Aliassime took the title in Florence, adding to his Rotterdam triumph from February.

Korda wrestled his way past a recently resurgent Dominic Thiem, scraping a 6-7 (4-7) 6-3 7-6 (7-4) victory, before Auger-Aliassime was given a mighty battle by veteran Frenchman Richard Gasquet, winning through in two tight sets, 7-6 (7-2) 7-6 (7-3) his margin.

Like Berrettini and Auger-Aliassime, Greece's Stefanos Tsitsipas has a third title of the year in his sights this weekend.

Tsitsipas swept through to the final of the Stockholm Open with a 6-2 6-2 win over Finland's Emil Ruusuvuori, setting up a clash with 19-year-old Danish player Holger Rune.

For Rune, there was no such straightforward path into the final as Alex de Minaur pushed him all the way, with the Australian eventually edged out 4-6 7-6 (7-1) 7-5 after two hours and 50 minutes.

Cameron Norrie fought back from a first-set loss against Aslan Karatsev to advance into the quarter-finals of the Stockholm Open, keeping hopes of qualifying for next month's ATP finals alive.

Norrie's return to action, having withdrawn from last month's Korea Open with illness, was not plain sailing as Karatsev won the first set tie-break 10-8 to put the Brit under pressure.

However, the 27-year-old responded by taking the next two sets 6-3 6-4 to seal safe passage, helped by six first-serve aces, which also maintains his hopes of a spot in November's finals and sets up a tie against 19-year-old Holger Rune.

Top seed Stefanos Tsitsipas was given a sterner test by Maxime Cressy before eventually securing a spot in the quarter-finals 7-6 (7-5) 7-6 (14-12) in a two-hour contest, while Denis Shapovalov also beat Antoine Bellier in straight sets.

The number one seed is through at the European Open in Antwerp as well as Hubert Hurkacz toppled Jack Draper 7-6 (7-5) 6-7 (5-7) 6-1.

Britain's Dan Evans eased into the final eight after securing a 6-2 6-1 victory against Constant Lestienne, while there were also victories for Yoshihito Nishioka and Richard Gasquet.

Elsewhere, sixth-seed Sebastian Baez was a 7-5 7-6 (7-3) winner against Lorenzo Sonego in the Napoli Open, where Roberto Carballes Baena and Corentin Moutet were among the other victors.

Novak Djokovic claimed the 90th ATP Tour title of his illustrious career after landing the Astana Open crown with a straight-sets victory over Stefanos Tsitsipas.

The Serbian also secured a place at next month's ATP Finals in Turin after prevailing 6-3 6-4 in just 75 minutes.

It was Djokovic's fourth piece of silverware of the season – adding to his triumphs in Wimbledon, Rome and Tel Aviv – and stretched his winning streak to nine matches.

The 21-time major winner had prevailed in each of his last six encounters with Tsitsipas and claimed a crucial break in game eight of the opening set, before serving it out to draw first blood.

Seeking his maiden ATP 500 title at the ninth attempt, Tsitsipas was aiming to join Djokovic in becoming only the second male player to win a tour-level title on all three surfaces this season.

However, the Greek ace hit 25 unforced errors throughout the contest to his opponent's seven and was broken again in game five of the second set.

Djokovic, who won 33 of his 38 first-serve points and did not face a single break point, subsequently sealed victory with a brilliant backhand winner to make it back-to-back titles following last week's triumph in Tel Aviv.

"I always hoped that I would be going to have a great career. Obviously, [I] didn't know the amount of finals I was going to play, the amount of tournaments I was going to win, but my intention was always to reach the highest heights in our sport.

"I'm just very grateful and blessed to be able to play this well at this stage of my life. I think the experience, probably, in these kinds of matches and big occasions helps as well to approach mentally in the right way.

"I could not ask for a better restart of the season. I'm super-pumped and motivated to end the season as well as I have done these past couple of weeks."

Novak Djokovic progressed to the Astana Open final after Daniil Medvedev retired from their last-four clash due to injury.

The two played out a thrilling first two sets, with Medvedev taking the lead before Djokovic fought back to level the match via a tie-break.

However, the Russian was unable to continue after sustaining a leg injury, keeping Djokovic in the hunt for back-to-back titles when he competes in the showpiece, where he will face Stefanos Tsitsipas.

"I really hope that his injury is nothing too serious,” said Djokovic. "I know Daniil, he's a great guy, he's a fighter, he's a big competitor.

"He wouldn't retire a match if he didn't feel that he [could] continue or [if it wouldn't] worsen his injury. He told me that he pulled an adductor muscle in his leg.

"It was such a close match, particularly in the second set. I would probably say he was a better player on the court in both sets. I was fighting and trying to find a way.

"I found a way to win the second, but I'm just sad for the tournament and for these people who were enjoying the battle, and for Daniil that it had to end this way."

Third seed Tsitsipas started slowly in the first set against Andrey Rublev but managed to triumph 4-6 6-4 6-3 in Saturday's other semi-final.

"My mentality kind of changed," said Tsitsipas, who will seek his first ATP 500 title at the ninth attempt. "I played with more of an aggressive game style and didn’t have anything by luck."

At the Japan Open, Taylor Fritz battled back from 3-1 down in the deciding set against Denis Shapovalov to claim a 6-3 6-7 (5-7) 6-3 semi-final victory and book his place in his third ATP Tour final this season.

Third seed Fritz faces an all-American clash in Sunday's final against Frances Tiafoe, who dropped his first set of the week as Soonwoo Kwon bageled him, but the US Open semi-finalist recorded a 6-2 0-6 6-4 win.

"It was a weird match, but I'm happy to get through," said Tiafoe, who progressed into his second final of the season and fifth overall.

"It's not always going to be pretty, it's not always going to be the best stuff, but a win is what matters."

Novak Djokovic set up a semi-final meeting with Daniil Medvedev at the Astana Open on Friday, cruising past Karen Khachanov in the last eight.

Djokovic complemented a fine display of serving by converting three of his five break points in a 6-4 6-3 victory, recording his seventh consecutive win following his absence from the US Open.

The 21-time grand slam champion has now reached six semi-finals this year, but saw room for improvement in his performance after beating the world number 18.

"I didn't play as well from the baseline as I did in the first two matches, but still it was enough," Djokovic said. "I managed to produce some good tennis when it was most needed in both sets."

Looking ahead to his final-four match, the Serb added: "I always expect highs from myself. Hopefully I can elevate still the level of my game for tomorrow, because it's going to be needed." 

Djokovic will face an 11th tour-level meeting with Medvedev in the next round after his fellow former world number one recorded a dominant 6-1 6-1 win over Roberto Bautista Agut.

On the other side of the draw, third seed Stefanos Tsitsipas beat Hubert Hurkacz 7-6 (10-8) 6-3, and will now face Andrey Rublev after he eased to a 6-1 6-2 win over Adrian Mannarino.

At the Japan Open, a knee injury forced Wimbledon runner-up Nick Kyrgios to withdraw from his meeting with Taylor Fritz, with the American set to take on Denis Shapovalov in the semi-finals.

Seventh seed Shapovalov saw off Borna Coric 6-4 6-3 to reach the final four, while fourth seed Frances Tiafoe advanced with a 6-0 6-4 win against Miomir Kecmanovic.

South Korea's Kwon Soon-woo claimed the final place in the semi-finals in Tokyo, beating Spain's Pedro Martinez 6-3 6-0

Carlos Alcaraz was dumped out of the Astana Open in the first round on Tuesday, suffering a surprise 7-5 6-3 defeat to David Goffin.

Goffin entered the draw as a lucky loser after squandering two match points to lose his final qualification match against Luca Nardi on Sunday, but he produced a fine display to see off the world number one in one hour and 46 minutes. 

The Belgian had to rediscover his composure to take the opener after throwing away a 5-2 lead, but ultimately deserved his straight-sets win over the US Open champion. 

Speaking on court after his victory, Goffin said: "I always believe that I have the level to cause some trouble against those guys. 

"When you play against the world number one on a big stage, big crowd, the fire inside gives you so much power to play your best tennis because you don't have any choice."

Stefanos Tsitsipas was the only other seed in action in Kazakhstan on Tuesday, and he advanced to the round of 16 by beating home favourite Mikhail Kukushkin 6-3 6-4.

The Tokyo Open also lost its top seed, as Casper Ruud fell to a 6-3 6-3 loss to Jaume Munar, who claimed his first top-10 win since beating Alexander Zverev in 2019.

But the likes of Borna Coric and Nick Kyrgios fared better, claiming straight-sets wins over Thanasi Kokkinakis and Tseng Chun-hsin, respectively.

Wimbledon runner-up Kyrgios only dropped four further points on his serve after being forced to save a break point in his opening service game, racing to a dominant 6-3 6-1 win.

Elsewhere, eighth seed Dan Evans fought back to beat Radu Albot 6-7 (3-7) 6-1 6-4, and Alex de Minaur lost 6-3 6-2 to Kwon Soon-woo. 

Felix Auger-Aliassime and Frances Tiafoe played starring roles as Team World won three matches on the spin on Sunday to claim a first Laver Cup triumph over Team Europe.

Team World went into the final day of action at the O2 Arena in London sitting four points behind their opponents, but they produced a stirring fightback to claim the trophy at the fifth time of asking.

Central to their success was Canadian Auger-Aliassime, who beat Novak Djokovic in singles after successfully teaming up with Jack Sock in the doubles.

Holding an 8-4 lead from Saturday, many expected Team Europe to breeze it from there, but John McEnroe's World team had other ideas and earned a 13-8 victory. 

Up first in the doubles were Auger-Aliassime and Sock, who lost the first set to Team Europe's Andy Murray and Matteo Berrettini.

However, the World duo roared back to deliver three points for their team by claiming a 2-6 6-3 10-8 victory.

Djokovic won two matches for Team Europe on Saturday, yet he was powerless to stop Auger-Aliassime in their singles clash. The 22-year-old Canadian landed a 6-3 7-6 (7-3) over the Wimbledon champion.

That moved Team World 10-8 ahead in the overall contest, setting the stage for a decisive clash between Stefanos Tsitsipas and Frances Tiafoe, with a further three points at stake.

Greek Tsitsipas won the first set, but 24-year-old American Tiafoe stormed back to win an epic tie-break in the second on his way to a 1-6 7-6 (13-11) 10-8 success.