The men's tennis tour has scrapped plans to stage four tournaments in China later this year as the pandemic continues to take its toll on the sporting calendar.

Mandatory quarantine rules make it unfeasible for international players and tour officials to travel to the events, including the Shanghai Masters, a top-tier ATP 1000 tournament.

The lucrative Shanghai event had been due to run from October 9-16 and would have featured many of the world's top players.

Also cancelled are the Chengdu Open and the Zhuhai Championships, which were scheduled to begin on September 26, and the China Open, billed for the following week.

The ATP said it had cancelled the three-week China swing "due to ongoing restrictions related to COVID-19".

It marks a third successive year in which the run of tournaments has had to be cancelled, with China last hosting ATP events in 2019, before the pandemic hit.

At the same time as it cancelled the tournaments in China on Thursday, the ATP made provision for its players to keep earning by announcing six new events to take place in September and October.

Those events will be played in San Diego, Seoul, Tel Aviv, Florence, Gijon and Naples, the ATP said, with all at ATP 250 level, the lowest rung of the main tour.

The WTA, which runs the women's tour, announced last December it would be suspending all its tournaments in China due to concerns over the wellbeing of Peng Shuai, a professional tennis player who appeared to allege she had been sexually assaulted by a powerful former government official.

Former doubles world number one Peng has since denied making the accusations, yet the WTA has remained concerned for her safety and freedom.

Novak Djokovic must be allowed to play at the US Open because a ban over his COVID-19 vaccination refusal would be "crazy", according to John McEnroe.

The Serbian won his seventh Wimbledon title this month, but the All England Club event was just his second major of the year after missing the Australian Open in January.

Djokovic was not permitted to play in the opening major of 2022, where issues surrounding his visa ended with him being deported from Melbourne on public health grounds due to not taking the vaccine.

The 35-year-old hopes to compete at Flushing Meadows in August but has insisted he will not take the vaccination, while the United States is refusing to allow unvaccinated foreigners to enter the country.

The USTA confirmed it would adhere to US rulings surrounding coronavirus protocols, despite including Djokovic on the entry list for the final slam of the year on Wednesday.

Seven-time major champion McEnroe has previously suggested Djokovic should be allowed to compete and reiterated his calls for the 21-time slam winner to be exempt from vaccination regulations.

 "I mean, we have to find a way to get Novak into the US Open," McEnroe told Tennis365.

"How can he not be there? He has just won Wimbledon, he is a great champion and he should be in the US Open.

"I don't agree with his decision not to get vaccinated, but I respect it. He is one of the fittest guys in the world and everything he puts into his body, he is watching carefully.

"Now we are saying that because of his choice, he can't play at the US Open. I mean, come on. He has already been deported from Australia for the same reason and here we are again."

For Djokovic to be allowed into the United States, it would require a change of tack from law-makers, or he would have to be considered suitable for an exemption.

Among those who would be eligible for such an exemption are "persons whose entry would be in the national interest".

"I hope someone finds a way to sort this out," McEnroe said. "It's crazy that Novak misses the US Open at this stage."

Anett Kontaveit cruised into the quarter-finals of the Hamburg European Open with a straight-sets win over Rebecca Peterson, while third seed Zhang Shuai was forced out of the Palermo Ladies Open through injury.  

World number two Kontaveit recorded a 6-3 6-2 victory over Peterson on the clay in Germany, setting up a last-eight meeting with eighth seed Andrea Petkovic. 

The Estonian's win was her third over Peterson and maintained her 100 per cent career record against Swedish opponents, taking her to seven such successes. 

Kontaveit was joined in the quarter-finals by fellow seeds Aliaksandra Sasnovich, who beat Aleksandra Krunic 6-3 6-2, and Maryna Zanevska, who downed Alexandra Cadantu-Ignatik 6-4 6-1. 

They will face off for a semi-final spot on Thursday, while Anastasia Potapova will meet 2021 French Open champion Barbora Krejcikova after beating Maria Carle in straight sets. 

At the Palermo Ladies Open, meanwhile, third seed Zhang withdrew from her last-16 clash with home favourite Jasmine Paolini before taking to the court, citing an unspecified injury. 

Fellow seeds Sara Sorribes Tormo and Anna Bondar both reached the quarter-finals with straight-sets wins, however, with the pair set to face off for a semi-final berth on Friday.  

Pablo Carreno Busta saw his title defence at the Hamburg European Open come to an early end as he crashed out on Wednesday, while Andrey Rublev progressed with ease.

Carreno Busta fell to a 6-3 1-6 7-6 (7-5) second-round defeat against Slovakian Alex Molcan, who progressed to a fourth ATP Tour quarter-final this season.

World number 48 Molcan will next meet Borna Coric after the Croatian eased past Tallon Griekspoor 6-3 6-4, registering back-to-back tour-levels wins for the first time in 17 months.

Second seed Rublev coasted through his first-round clash with Ricardas Berankis, triumphing 6-3 6-4 as he improved his record at the ATP 500 clay-court event in Germany to 10-2.

"I am happy with my performance. Ricardas is a really tough player," said world number eight Rublev, who is aiming for his fourth title of the season after success in Marseille, Dubai and Belgrade.

"He hits the ball really hard and plays fast, so I had to bring intensity from the first game. I am really happy with how I was serving today and I hit some great shots from the baseline.

"The game he broke me in the second set he played really well. He returned really aggressively and I don’t think I made one first serve. But then I kept [my] focus and broke him straight away again."

Alejandro Davidovich Fokina was another comfortable winner, easing past Jozef Kovalik 6-2 6-2 to set up a quarter-final contest with Lorenzo Musetti, who beat Emil Ruusuvuori 6-4 7-5.

Play was suspended early at the Swiss Open due to bad weather, with Spaniard Jaume Munar downing Alexander Ritschard 6-3 6-3 in the only match of the day to reach the last eight.

That meant top seed Casper Ruud will have to wait until Thursday to face Jiri Lehecka in Gstaad, with third favourite Roberto Bautista Agut also seeing his match with Juan Pablo Varillas pushed back a day.

Serena Williams has been named on the entry list for the US Open.

The 23-time grand slam champion withdrew from last year's tournament at Flushing Meadows with a torn hamstring, but she has entered this year's with a protected ranking of 16.

Williams has also been named among the initial entry list for August's Cincinnati Masters as she returns to the US Open Series.

Former US Open champions Naomi Osaka, Bianca Andreescu and Emma Raducanu will also be present in Ohio.

Williams returned to action after almost a year away from the game in the WTA event in Eastbourne in June in the women's doubles, before competing in the singles at Wimbledon.

Following an exciting defeat to Harmony Tan in the first round on Centre Court at SW19, Williams said she was aiming for a US Open return. 

"When you're at home, especially in New York, and the US Open, that being the first place I've won a grand slam, is something that's always super special" she said. "There's definitely lots of motivation to get better and to play at home."

The 40-year-old will also compete at the Canadian Open next month as she ramps up her preparations for the US Open.

Novak Djokovic looks set to miss the US Open after the USTA confirmed it would respect the United States government's policy regarding unvaccinated travellers from outside the country. 

Djokovic has already missed one grand slam this year, with the 21-time major champion absent from the Australian Open after a protracted saga surrounding his visa ended with him being deported on public health grounds. 

The Serbian was permitted to play at the French Open and Wimbledon, winning the latter for the seventh time in his career, despite being unvaccinated against COVID-19. 

However, he is unlikely to have a chance to compete for a fourth singles title at Flushing Meadows. 

Djokovic was included on the entry list for the final slam of 2022, but the U.S. government does not permit unvaccinated non-U.S citizens to enter the country. 

In a statement released alongside the entry lists, the USTA said: "Per the ITF Grand Slam rulebook, all eligible players are automatically entered into the men's and women's singles main-draw fields based on ranking 42 days prior to the first Monday of the event. 

"The US Open does not have a vaccination mandate in place for players, but it will respect the U.S. government's position regarding travel into the country for unvaccinated non-U.S. citizens." 

Should Djokovic miss the New York major, it will mean he will not get the chance to play in a grand slam until the 2023 French Open. 

Having had his visa to enter Australia cancelled, Djokovic is banned from re-applying for three years. Unless that ban is reversed or reduced, the 35-year-old may well have played his final Australian Open. 

Djokovic is one major title shy of Rafael Nadal's record of 22 following his four-set win over Nick Kyrgios in the Wimbledon final. 

He reached the final of last year's US Open but lost to Daniil Medvedev in straight sets, preventing him from claiming the calendar Grand Slam. 

A month later, the White House issued a presidential proclamation declaring that non-U.S. citizens must be vaccinated to enter the country, effectively ending his hopes of going one better in 2022. 

Venus Williams will make a long-awaited singles comeback at the Canadian Open next month.

The seven-time grand slam champion has not played a singles match since she lost to Hsieh Su-Wei in the first round at the Chicago Women's Open last August.

But she returned from a leg injury to partner Jamie Murray in the mixed doubles at Wimbledon earlier this month, reaching the second round.

The 42-year-old will be back in singles action in Toronto, where the Canadian Open begins on August 8.

Williams' sister, Serena, will also play in the tournament three weeks before the US Open gets under way.

After being handed a wild card, Venus will join the likes of world number one Iga Swiatek in a strong field.

The American made her debut in the hard-court event as a 15-year-old back in 1995, losing to Sabine Appelmans in the first round.

Anett Kontaveit and Barbora Krejcikova both breezed through at the Hamburg European Open, while Yulia Putintseva eased into the Palermo Ladies Open second round.

Top seed Kontaveit overcame world number 61 Irina Bara in straight sets in her first-round clash and third favourite Krejcikova followed suit in her second-round match against Poland's Magdalena Frech.

Kontaveit will meet Sweden's Rebecca Peterson in the next round as she looks to set up a quarter-final meeting in Germany with eighth seed Andrea Petkovic, who defeated Misaki Doi 6-4 6-3 on Tuesday.

There was no such luck for ninth seed Elena Gabriela Ruse, though, after she lost 6-0 6-4 to last week's Budapest Grand Prix winner Bernarda Pera.

Swiss Joanne Zuger will next be the next challenge for Pera as she aims to reach a quarter-final clash against Katerina Siniakova, who triumphed 6-1 6-1 over Brazil's Laura Pigossi.

Putintseva is ranked as the second favourite in Italy and progressed with ease from her first-round clash against world number 147 Jaimee Fourlis, winning 6-3 6-1.

Seventh seed Anna Bondar had little difficulty beating Clara Burel 6-4 6-4, though Caroline Garcia and Nuria Parrizas Diaz faced more difficult tasks in their respective openers.

France's Garcia, the fifth favourite in Palermo, responded to a first-set scare to defeat compatriot Chloe Paquet, while eighth seed Parrizas Diaz also lost her opening set before downing Asia Muhammad.

Carlos Alcaraz was made to come from a set down but finally overcame Nicola Kuhn in the first round of the Hamburg European Open.

The highly rated Spanish teenager eventually downed the German wildcard 3-6 6-1 7-6 (7-3).

Kuhn, ranked 259 in the world, was aggressive early on against Alcaraz, and was rewarded with the first set.

But the 19-year-old – playing as top seed in an ATP Tour event for the first time – rallied to ease through the second set, before being made to work much harder to clinch the win on a tie-break.

Alcaraz will now play Filip Krajinovic in the second round after the Serbian also won in a third-set tie-break against Sebastian Baez 6-1 4-6 7-6 (8-6).

Three seeded players crashed out on Tuesday in straight sets, with third favourite Diego Schwartzman losing against Emil Ruusuvuori 7-5 6-4, sixth seed Nikoloz Basilashvili beaten by Aslan Karatsev 6-4 6-0, and eighth seed Holger Rune going down 7-6 (10-8) 7-5 to Tallon Griekspoor. 

Fourth seed Pablo Carreno Busta eased through against Luca Nardi 6-2 6-1, while there were also wins for Fabio Fognini, who sealed his 400th career victory, as well as Daniel Elahi Galan, Borna Coric and Francisco Cerundolo.

At the Swiss Open in Gstaad, sixth seed Cristian Garin lost 6-3 6-4 to Yannick Hanfmann and seventh favourite Hugo Gaston fell to Dominic Thiem despite winning the first set, losing 1-6 6-1 7-6 (9-7).

Elsewhere, Frenchman Richard Gasquet beat Roberto Carballes Baena 7-5 6-4, while his compatriot Benoit Paire retired hurt when a set and a break down against Elias Ymer.

A tight game between Swiss pair Dominic Stricker and Marc-Andrea Huesler saw the former prevail 6-7 (2-7) 7-6 (7-2) 6-4, and an all-Spanish affair was similarly close as Jaume Munar defeated Bernabe Zapata Miralles 6-3 3-6 7-5.

There were also wins for qualifiers Juan Pablo Varillas and Nicolas Jarry against Lorenzo Sonego and Thiago Monteiro respectively.

Daria Kasatkina revealed she is in a gay relationship as Russia's leading star on the WTA Tour attacked homophobic attitudes in her homeland, and called for the war in Ukraine to end.

In an emotional interview with documentary maker Vitya Kravchenko, Kasatkina, who lives in Barcelona, teared up at the prospect of potentially being unable to return to Russia after being so candid.

The recent French Open semi-finalist has won four WTA titles in her career, including trophy runs at the Kremlin Cup in Moscow and the St Petersburg Open.

She has spoken about matters of sexuality in the past, and when asked whether she has a girlfriend, Kasatkina said in the new documentary: "Yes."

On her social media accounts, Kasatkina confirmed she and Olympic figure skater Natalia Zabiiako, who she described as "my cutie pie", are a couple.

She knows LGBT matters are taboo in Russia, saying: "So many subjects are taboo in Russia, some of them more important than ours, it's no surprise.

"This notion of someone wanting to be gay or becoming one, so ridiculous I think. There's nothing easier in this world than being straight.

"Seriously, if there is a choice, nobody would choose being gay. Why make your life harder, especially in Russia? What's the point?"

Asked whether she would be able to hold hands with her girlfriend in Russia, Kasatkina said: "Never."

Assessing the process of coming out, the 25-year-old said: "It's up to you how to do it and how much to tell. Living in peace with yourself is the only thing that matters, and f*** everyone else."

Few Russian sports stars have spoken out against the invasion of Ukraine, but Kasatkina made it clear that she feels strongly the war must stop.

Asked what she wanted most of all, Kasatkina said: "For the war to end. There hasn't been a single day since February 24 that I haven't read some news myself. Or haven't thought of it. [I want] for the day to just pass by without it.

"What people go through there, people that have relatives in Ukraine, especially when you start talking about Russia, Belgorod, here we go again. I can't imagine what they're going through, it's a full-blown nightmare.

"If only we could do something to stop that, even tiny percentage to stop. Not to change people's minds or something, only stop. Without a thought, I'd do anything, but unfortunately that's impossible and I think you understand it. We can't affect it. We can't change events that unfold. You feel powerless."

When she was asked by Kravchenko whether she was afraid she might not be allowed back to Russia because of her criticism, Kasatkina said: "Yes, I have thought about it."

She broke down in tears at that point.

Kasatkina has found support for coming out, with former doubles star Pam Shriver among those thanking her. She was also praised by Russian women's national team footballer Nadya Karpova, who has spoken about her own lesbian life and has also been a critic of the war.

Karpova posted on Instagram: "You are beautiful! I'm proud."

Kasatkina thanked Karpova in the YouTube documentary, saying: "Not only did Nadya help herself by coming clean and getting this burden off her chest, but she helped others.

"I believe it's important the influential people from sports, or any other sphere really, speaks about it. It helps."

Four-time grand slam champion Naomi Osaka will play her first tournament since the French Open at the Silicon Valley Classic after accepting wild card. 

The 24 has won a grand slam in each of the past four years, but crashed out in the first round at Roland Garros with a defeat to Amanda Anisimova – who also knocked her out of the third round of the Australian Open – before withdrawing from Wimbledon due to an injury concern.

Ir was announced on Monday that Osaka will make her return in hard-court event in San Jose that starts on August 1 - four weeks before the US Open gets under way.

Silicon Valley Classic tournament director Vickie Gunnarsson said it was a great outcome to add Osaka to the playing field in the competition where it all began for her.

"We are very excited to have Naomi Osaka returning to the Bay Area," she said. "She made her WTA debut at our event and watching her grow both on and off the court has been amazing.

"She is not only an incredible player but her commitment to equality and social change is truly inspiring."

Osaka is down in 38th place in the rankings and has not won a tournament this year, but reached the final of the Miami Open in April, losing to world number one Iga Swiatek.

Already confirmed for the Silicon Valley Classic are Wimbledon champion Elena Rybakina, world number five Ons Jabeur, young American star Coco Gauff and 2019 US Open champion Bianca Andreescu.

Barbora Krejcikova beat Suzan Lamens in the opening round of the Hamburg European Open for her first victory on clay in over a year.

The third seed, who claimed a second Wimbledon women's double title this month, saw off qualifier Lamens 6-2 6-4 to reach the last 16.

Her most recent victory on a clay-court surface prior to Monday came at last year's French Open, winning both the singles and women's doubles titles at Roland Garros in 2021.

Last year's runner-up Andrea Petkovic is also through thanks to a 6-3 6-3 victory over Tamara Korpatsch and will now face Misaki Doi, who defeated Oksana Selekhmeteva.

At the Palermo Ladies Open, meanwhile, fourth seed Sara Sorribes Tormo battled back from a set down to overcome Ana Bogdan 2-6 6-4 6-2.

Third seed Zhang Shuai also avoided an upset as she secured a 7-6 (7-3) 7-6 (9-7) victory over Rebeka Masarova, while Irina Begu required three sets to beat Marina Bassols.

Alejandro Davidovich Fokina sprung a surprise in the first round of the Hamburg European Open as he knocked out fifth seed Botic van de Zandschulp.

Van de Zandschulp reached the round of 16 at Wimbledon before losing Rafael Nadal, and he was undone by another Spaniard on the clay in Germany.

Davidovich Fokina broke Van de Zandschulp's serve six times en route to a 6-4 6-4 victory.

He will next face qualifier Jozef Kovalik, who also progressed on Monday alongside Slovakian compatriot Alex Molcan.

Lorenzo Musetti prevailed in three sets against Dusan Lajovic, while Karen Khachanov went the distance in beating Jan-Lennard Struff.

There was a shock at the Swiss Open Gstaad as home wild card Alexander Ritschard knocked out eighth seed Joao Sousa in straight sets.

Fifth seed Pedro Martinez beat fellow Spaniard Carlos Taberner, while there were also wins for Federico Delbonis and Jiri Lehecka.

Maxime Cressy staged an impressive fightback in the Hall of Fame Open final to outlast Alexander Bublik and scoop his first ATP Tour title.

When he trailed by a set and 3-0, Cressy's hopes looked almost forlorn, yet the French-American came back to win 2-6 6-3 7-6 (7-3) in two hours and 23 minutes.

The run of six consecutive games in the second set saved Cressy's skin, before he edged a decider against Russian-born Kazakh rival Bublik in which neither man could force a break of serve.

Cressy had a brief injury timeout near the end of the third set, before sweeping through the tie-break.

The grass-court tournament in Newport, Rhode Island, earlier saw Lleyton Hewitt inaugurated to the International Tennis Federation's Hall of Fame, with the former US Open and Wimbledon champion on hand to receive the accolade.

Hewitt won the last ATP title of his career at the Hall of Fame Open in 2014, having lost in the final in the previous two seasons.

The 41-year-old Australian described the Hall of Fame entry on Sunday as "an incredible honour", saying he had previously considered it out of his reach and "for the people that were my idols growing up and the absolute legends of the sport".