Stan Wawrinka said he was "feeling great" after securing his first win in 15 months by downing 14th seed Reilly Opelka at the Internazionali d'Italia.

The three-time grand slam winner made his tour return last month after requiring two surgeries on a left foot injury, but rallied after losing his first set against Opelka to secure a memorable 3-6 7-5 6-2 first-round victory.

Speaking after booking a second-round meeting with Laslo Djere, who beat Borna Coric 6-2 6-7 (3-7) 6-2, Wawrinka said his desire to play at the top level never left him, despite his injury woes.

"I think in general I was feeling good on the court, physically I was feeling great," he said. "For sure, when you don't win a match in more than a year, you start to think about it more than you should and not focus on the right things. 

"In general, I think it was a great match, a great battle. I stayed positive. I started to feel much better with my tennis by the end of the second set, and in the third set. I'm really happy with this victory.

"After two surgeries, at my age I could easily have stopped playing because my career is way better than what I expected when I was young.

"But I still have this fire in me. I still believe that I can play great tennis. I still believe that I make some big results, maybe not now, but in a few months."

Fellow former grand slam champion Dominic Thiem, who also returned from a long injury-enforced absence last month, fared less well, going down in straight sets to Fabio Fognini.

Having lost to Andy Murray at the Madrid Open last time out, 2020 US Open winner Thiem is still chasing his first victory of the year after losing 6-4 7-6 (7-5) to the 34-year-old Italian.

Elsewhere, 13th seed Denis Shapovalov edged an epic three-hour contest against Italy's Lorenzo Sonego 7-6 (7-5) 3-6 6-3, responding after being handed a game penalty for shouting expletives at a partisan crowd in Rome during the second set.

The frustrated Canadian was heard to tell spectators: "Shut the f*** up" when being booed after complaining about a second serve being called out by the umpire, but eventually regained his composure to claim a three-set win.

Shapovalov will face Georgia's world number 25 Nikoloz Basilashvili in the second round after he overcame Daniel Evans 7-6 (7-2) 6-2, while the only other seed to play on Monday, Spain's Pablo Carreno Busta, cruised to a 6-3 6-2 victory over Federico Delbonis.

Andy Murray swept aside Dominic Thiem in impressive fashion to secure his first clay-court win in five years as the Scot advanced to the second round at the Madrid Open on Monday.

The three-time grand slam champion was largely in control against his Austrian opponent, hitting nine aces and saving all three break points against his serve, while Thiem could only save one of the three he faced as Murray won 6-3 6-4.

He will now play 14th seed Denis Shapovalov after the Canadian beat Ugo Humbert 7-6 (7-1) 6-3.

The winner of that contest will have a last-16 meeting against the victor of Novak Djokovic and Gael Monfils after the latter eased into the round of 32 to set up a clash with the Serbian.

Monfils defeated wildcard Carlos Gimeno Valero 6-3 6-0 in less than an hour, while Alejandro Davidovich Fokina also advanced with a 7-5 6-3 win against Lloyd Harris.

Dusan Lajovic set up a second-round match against fifth seed Casper Ruud, who defeated Borna Coric 6-3 4-6 6-4, and ninth seed Cameron Norrie will go up against John Isner, the Briton having overcome Soonwoo Kwon 7-5 7-5.

An interesting tie awaits the much-talked about Carlos Alcaraz after Nikoloz Basilashvili beat Fabio Fognini 7-5 6-4, with the Georgian to face the number seven seeded teenager next.

Jannik Sinner, the 10th seed, scraped through a hard-fought encounter against American Tommy Paul 6-7 (4-7) 7-6 (7-4) 6-3, and will play Alex de Minaur next after the Australian beat Pedro Martinez 7-6 (7-2) 1-6 6-3.

Diego Schwartzman will take on Grigor Dimitrov in the second round. The Argentine 13th seed beat Benoit Paire 6-2 6-7 (5-7) 6-1, while Dimitrov overcame Maxime Cressy 6-2 7-6 (7-4).

Dominic Thiem is ready to "get back on track" after testing negative for coronavirus.

The luckless Austrian revealed he had contracted COVID-19 after making a long-awaited return in the Andalucia Open Challenger Tour event last week.

Thiem has not played on the ATP Tour since last June, missing Wimbledon and the US Open in 2021 after undergoing wrist surgery.

The 2020 US Open champion, who was beaten by Pedro Cachin on his comeback in Marbella, on Thursday stated that he is now COVID-free.

"A short update: I am finally negative and I feel much better! Thank you for all your messages! I really appreciate it!" he tweeted.

"I'm going to have a medical check-up, so I can get back on track!"

Thiem has reportedly pulled out of the Monte Carlo Masters this week, but his return to the ATP Tour should be imminent with the French Open on the horizon next month.

Dominic Thiem's bad luck continued as the former world number three confirmed he has tested positive for COVID-19.

Thiem only made his return to action on Tuesday, having not featured on the ATP Tour since June last year.

The Austrian underwent surgery on a wrist injury that kept him out of Wimbledon and also prevented him from defending his US Open title, while he also missed this year's Australian Open.

Having opted to push back his comeback further by skipping Indian Wells and the Miami Open, Thiem instead decided to play at the Challenger Tour's Andalucia Open.

His return was short-lived, as Thiem went down 6-3 6-4 to Pedro Cachin.

And Thiem will now face another spell out, after revealing he has contracted coronavirus.

"Looks like lately the good news don't last long... last night after dinner, I started feeling unwell and didn't have a good night," Thiem wrote on his official Instagram account.

"After developing mild symptoms I decided to take a test this morning, which came back positive for COVID-19.

"Now I have to wait and see how it develops. I'll keep you posted. Thank you all in advance for your support!"

Former US Open champion Dominic Thiem made his long-awaited return from a wrist injury on Tuesday, but lost 3-6 4-6 to Pedro Cachin at an ATP Challenger event in Marbella.

Thiem, the former world number three who hasn't played since 2021, started slowly and fell 5-0 behind in the first set against the world number 228.

He improved in the second set but was not able to recover from dropping serve in the first game.

"Obviously, the result today is the bitter part," Thiem posted on his Instagram. "I would have wanted to win, and I have to accept the defeat in a humble manner.

"This is only the beginning of a long way to the top of my game."

Dominic Thiem was forced to delay his comeback as he withdrew from the Cordoba Open due to injury.

The former world number three has not played on the ATP Tour since damaging his wrist in Mallorca last June but was due to face Tomas Martin Etcheverry or Nicolas Jarry in Argentina.

However, the 2020 US Open champion confirmed on Monday: "In the last days, I suffered a minor injury between my knuckles, a little strain of my ligament.

"The positive thing is the wrist is perfectly fine, but I'm suffering pain in my hand and also lacking practice, so I have to pull out.

"I'm very sad, but I'm going to come back once I'm 100 per cent fit, and thank you so much for the great and warm welcome I had here in Cordoba."

Thiem's withdrawal makes for a potentially simpler quarter-final draw for Pedro Martinez, who came through a marathon contest on Monday against Thiago Monteiro.

The eighth seed, who will next face Juan Ignacio Londero, won 4-6 6-4 7-6 (7-4) in a match lasting just under three hours.

There was an even longer battle between Juan Pablo Varillas and home favourite Facundo Bagnis, who was defeated 6-4 5-7 7-6 (7-5) after three hours and 17 minutes on court. Varillas will play Albert Ramos-Vinolas or Andrej Martin in the next round.

Jaume Munar also sealed his progress, defeating Benoit Paire in straight sets. 

Dominic Thiem has withdrawn from next month's Australian Open.

Thiem has not played on the ATP Tour since suffering a wrist injury at the Mallorca Championships in June.

The 2020 US Open champion was due to feature in the Mubadala World Tennis Championship in Abu Dhabi this month, but withdrew after suffering a setback.

Thiem on Tuesday revealed his wrist is in "optimal condition", but the Austrian will miss the first grand slam of the year at Melbourne Park and will instead make his comeback at the Cordoba Open next month.

The Austrian tweeted: "As you all know, I came back home to Austria to recover after hard practice sessions I had in Dubai and the slight setback in my preparation. I am now feeling well again, my wrist is in optimal condition and I am practicing normally with a very good intensity.

"After my short holidays, my team and I have assessed all matters and we have decided to make some changes to my initial tournament schedule.

"I will start the season in South America at the Cordoba Open in Argentina, end of January, and therefore I will not play this year at the Australian Open in Melbourne, a city that I love and where I have great memories of unforgettable matches in front of amazing crowds. I will miss the Australian fans but I will be back in 2023.

"We believe this is the right decision in order to have a good return to competition. For the moment I will remain in Austria for a few more days and then head to practice outdoors and get ready for my first event of the season."

The 28-year-old was a runner-up in the 2020 Australian Open before going on to claim his first major title at Flushing Meadows.

Dominic Thiem will skip the Australian Open if he is not happy with his fitness at the end of December, the former US Open champion said on Sunday.

The 28-year-old has not played on the ATP Tour since suffering a wrist injury at the grass-court Mallorca Championships in June.

Thiem missed Wimbledon and could not defend his grand slam title at Flushing Meadows, with injury fears lingering ahead of the new season.

Despite not requiring surgery on the damaged wrist, Thiem has been unable to play competitively and experienced a fresh setback this month when he pulled out of the Mubadala World Tennis Championship, an exhibition event in Abu Dhabi.

In announcing that decision on December 14, Thiem said he was "not yet ready to compete at the highest level", and there was little to inspire confidence when he issued an update confirming he would not travel to play in two events ahead of the Australian Open.

Although Thiem still wants to play at Melbourne Park, where the slam begins on January 17, his prospects are hinging on him feeling significantly more optimistic about his game and fitness in a matter of days.

Thiem wrote: "After speaking to my team, we have decided to return to Austria, instead of flying directly to Australia.

"Unfortunately, I caught a cold [and tested negative for COVID-19] while in Dubai and was unable to practise last week. I will therefore not be in the physical condition required to be able to play the ATP Cup and Sydney ATP 250.

"After not competing for the last six months I can't take the risk of coming back too soon and picking up a further injury.

"Overall, the time I spent in Dubai was great as I've increased the intensity and level of practise and my wrist is almost at 100 per cent.

"My aim is still to play the Australian Open but we will make a final decision about my participation by the end of December."

Dominic Thiem's comeback has been further delayed as the 2020 US Open champion does not feel ready to return at this week's Mubadala World Tennis Championship.

Austrian star Thiem has been out of action since suffering a wrist injury at the Mallorca Championships in June.

The 28-year-old missed Wimbledon and was unable to defend his title at Flushing Meadows, but he appeared to be on course to make his comeback before the end of 2021 after revealing in October he does not require surgery on his wrist.

However, the world number 15 is now facing a battle to be back to full fitness for January's Australian Open after withdrawing from an exhibition event in Abu Dhabi.

"I was looking forward to making my return to competition at Abu Dhabi but I feel that I am not yet ready to compete at the highest level," the 17-time ATP Tour champion posted via Twitter on Tuesday.

"It's disappointing to not take part this year but I need to continue my preparation for the upcoming season."

Thiem follows Casper Ruud in pulling out of the tournament, which begins on Thursday, while Emma Raducanu is out of the women's singles after testing positive for coronavirus.

Dan Evans and Taylor Fritz have taken the places of former world number three Thiem and Ruud, joining Andrey Rublev, Denis Shapovalov, Andy Murray and defending champion Rafael Nadal in the draw.

Dominic Thiem has confirmed he has been given a coronavirus vaccine and will return to action in Abu Dhabi next month with the objective of playing in the 2022 Australian Open.

The 2020 US Open champion has been out of action since suffering a wrist injury at the Mallorca Championships in June.

Thiem on Tuesday revealed he has made good progress with his recovery and will play in the World Tennis Championship, an exhibition event that will be staged from December 16-18.

The 28-year-old had stated he wanted to wait for a Novavax jab, but was urged by Austrian minister for Social Affairs, Health, Care and Consumer Protection Wolfgang Muckstein to take an alternative vaccine as his preferred choice would not be available until next year.

Thiem says he has now been vaccinated and is relishing getting back on court as he eyes a grand slam return in Melbourne in January.

"I am very happy to announce that my recovery is going well. The MRI I did today showed that my wrist injury has improved significantly," Thiem tweeted on Tuesday.

"A couple of weeks ago I started playing with soft balls and was able to switch to normal tennis balls during yesterday's practice session. My team and I strongly believe that I'll be ready to make my comeback later this year.

"I'll be returning to competition in December and will be playing the MWTC 2021 in Abu Dhabi – with the objective to return to the Tour for the 2022 Australian Open.

"Needless to say that the vaccine is needed to play both events, and in my case I have already been vaccinated. I saw recently some news about this and I had to make it very clear that I would get vaccinated. Hopefully the next time things won't be taken this far [sic] as I saw last week..."

Rafael Nadal is also set to return from injury in Abu Dhabi.

Novak Djokovic was "playing for history" and suffered from nerves in his US Open final defeat to Daniil Medvedev, according to previous champion Dominic Thiem, who backed the 34-year-old to return "stronger than ever" in 2022.

Medvedev prevented Djokovic from becoming the first man since Rod Laver in 1969 to win all four grand slams in a single year, beating him 6-4 6-4 6-4 in Sunday's thrilling showpiece.

Djokovic was seen in tears during the third set as his hopes of adding the US Open to his run of wins at the Australian Open, French Open and Wimbledon this year slipped away.

But Thiem tipped Djokovic to bounce back from the disappointment of defeat and return in 2022 even stronger.

"One unbelievable goal slipped out of his hands yesterday," Thiem told Stats Perform.

"I expect him to be as strong as ever in 2022. I think after he won in Roland Garros, everybody was only talking about the calendar slam – first about the golden slam, and then about the calendar slam.

"He [Djokovic] was under pressure. Nobody can feel that or anything like that because of it being the calendar slam.

"I can feel it in a smaller way, probably from last year's final and from some other matches. And at some points it's just getting to you. And so, I really felt for him as well towards the end of the match.

"So, it can happen that it also makes him even stronger next year when all these talks and all this pressure is not that big anymore."

Thiem, who missed the tournament with a wrist injury that will rule him out until 2022, believes nerves were a factor in Djokovic's defeat but agreed with Medvedev's assessment of the Serbian as the greatest of all time – though he could not set him apart from Roger Federer and Rafael Nadal.

"For me, there are three GOATs in the game, and each of them has achieved something very unique," Thiem said of the trio locked on 20 major titles each.

"So it's still the same for me as it was before. The three of them are the best in the history to me.

"And I'm only super happy to be in the same era with them and to be able to compete with them. Hopefully many more times next year again."

Dominic Thiem believes Emma Raducanu's sensational US Open triumph might be the "greatest breakthrough performance of all time".

Raducanu, 18, overcame fellow teenager Leylah Fernandez 6-4 6-3 on Saturday to cement her place in history.

Her triumph meant she became the first qualifier – male or female – in tennis history to win a grand slam final.

She did not lose a set in 10 matches across qualifying and the main draw, becoming the first player since Serena Williams in 2014 to win the US Open without dropping a single set.

Raducanu – whose first grand slam appearance only came at Wimbledon in June – was ranked 150th in the world before the US Open, but her stunning win in New York has seen her break into the top 30.

Thiem, who missed the men's tournament with a wrist injury, was in awe of Raducanu's stunning run at Flushing Meadows and says he can scarcely recall a more impressive breakthrough in the sport.  

"There were some other great achievements in the past but with Emma Raducanu, starting in the qualifiers and then playing such great tennis and making this incredible path, it's definitely, maybe, the greatest breakthrough performance of all time," he exclusively told Stats Perform.

"It's an incredible journey if you look at the stats. She didn't lose one set the whole tournament. She came from qualifying and she didn't even play one tie-break. That's simply amazing and something that was probably never witnessed before.

"And also the way she plays, her technique, the way she moves, somehow she brought it up to a new level for the whole game and it was great to see.

"But as well, her opponent, it was so fun to watch her. I was excited for it, watching every single point on TV. And it was great not only for women's tennis, but for all sports in general."

Nick Kyrgios, John Isner and Reilly Opelka have been named by Team World captain John McEnroe as his final three picks for the Laver Cup.

The trio join Denis Shapovalov, Felix Auger-Aliassime and Diego Schwartzman for the team event which runs from September 24-26 at TD Garden in Boston.

Laver Cup newcomer Opelka rose to a career-high world number 23 ranking en route to his first ATP Masters 1000 final in Toronto and defeated world number three Stefanos Tsitsipas, who will play for Bjorn Borg's Team Europe.

Isner, who has featured for Team World since the inaugural event in 2017, reached the semi-finals in Toronto and claimed his 16th ATP Tour title in Atlanta at the start of August.

He described the Laver Cup as "a highlight of my year", adding: "To be on a team with guys we're normally competing against is so different and so much fun. We come together so well as a group, the chemistry is awesome and it's such a great environment to be part of."

Australian firebrand Kyrgios is a striking inclusion in Team World's roster, while Team Europe will be without their big three: Roger Federer, Rafael Nadal and Novak Djokovic.

Federer and Dominic Thiem were expected to take part in this year's event, though both were forced to withdraw with injuries.

However, Borg's men still boast six of the world's top 11. World number two Daniil Medvedev leads the line-up, with Tsitsipas and Tokyo Olympics gold medallist Alexander Zverev for company.

Casper Ruud, who collected a 14th win in his last 15 completed matches on tour when he beat Opelka on Wednesday, will feature, while Andrey Rublev and Wimbledon finalist Matteo Berrettini complete the six-man team.

Team Europe have landed the title in each of the three editions of the tournament so far, with Prague, Chicago and Geneva having served as hosts.

Defending US Open champion Dominic Thiem will miss this year's tournament with a wrist injury that will rule him out until 2022.

The 27-year-old suffered the setback at the Mallorca Open in June and also withdrew from Wimbledon and the Tokyo Olympics.

World number six Thiem won his maiden grand slam at Flushing Meadows last year with victory over Alexander Zverev in a five-set thriller, but he will not get the chance to defend his title in New York.

"Having spent a week training on court, I still felt pain in my wrist and I knew that it was not 100 per cent," Thiem posted in a statement on his Twitter page on Wednesday.

"I went to see my doctors again and we have decided to follow a conservative treatment, giving the injury more time to recover.

"I'm very disappointed not to be able to defend my US Open title and to miss the rest of the season.

"But I know this is what I have to do. I have a long career ahead of me, so I will only come back once I'm fully recovered and in good shape to compete."

Thiem has a record of nine wins and nine losses this season, with his best result coming at the Madrid Open in May when reaching the semi-finals.

Twenty-time grand slam winner Roger Federer last week pulled out of the US Open, which runs from August 30 until September 12, after undergoing knee surgery.

Dominic Thiem has been ruled out of Wimbledon after tests on a wrist injury and faces a race to be fully fit in time to defend his US Open title.

The world number five retired from his match against Adrian Mannarino in the Mallorca Championships on Tuesday, when 5-2 up in the opening set.

Checks on the wrist by a specialist in Barcelona have shown Thiem needs time away from tennis, meaning Wimbledon is off the table along with tournaments in Hamburg and Gstaad in July.

According to a medical bulletin issued on Thiem's social media accounts, it will be five weeks before he can remove a wrist splint and begin to step up his recovery.

With the US Open beginning on August 30, that does not leave a lot of time for Thiem to recover physical fitness and find his best tennis. He would have been seeded number four at Wimbledon.

The medical bulletin read: "Tests found that there is a 'detachment of the posterior sheath of the ulnar side of the right wrist', an injury that will not allow him to compete in the circuit for several weeks.

"Thiem will wear a wrist splint for five weeks before beginning a progressive process of specific, functional rehabilitation to regain mobility as well as muscle strength in his wrist and ultimately return to training on court."

Thiem, who had already decided against playing at the upcoming Tokyo Olympics, appears to be hoping his lay-off is not as long as the experts have forecast.

He will undergo MRI scans and tests as his recovery progresses, and the 27-year-old Austrian said: "I'm going to do everything the doctors say in order to recover as quickly as possible.

"They've informed me that I might be out for several weeks, but I will do my best to be back on court soon.

"I'm really sorry for pulling out of the upcoming three tournaments I had in my calendar: Wimbledon, Hamburg and Gstaad.

"They are very important tournaments for me. I appreciate all the support from the fans in these difficult moments – I'm determined to come back stronger."

Thiem's absence is another blow for Wimbledon, with Rafael Nadal and Naomi Osaka having already announced they would not be playing the tournament.