Novak Djokovic is delighted to be back in competitive action after he booked his spot in the quarter-finals of the Dubai Tennis Championships.

Djokovic, whose decision not to be vaccinated against COVID-19 caused him to be deported from Australia on the eve of the year's first grand slam, eased to a 6-3 6-3 win over Lorenzo Musetti in his first match and made similarly light work of Karen Khachanov on Wednesday.

The world number one has won in Dubai on five occasions, last doing so in 2020, having elected against defending his title last year.

However, the Serbian is looking good to regain the crown in what is his first tournament on the ATP Tour in 2022, after he was unable to feature in Melbourne. 

Djokovic needed 98 minutes to see off Khachanov 6-3 7-6 (7-2) and tee up a quarter-final tie against qualifier Jiri Vesely.

"I missed it [playing competitively]. This is my life," Djokovic said, with his previous competitive appearances coming in the Davis Cup Finals in November and December.

"This is what I have known for the past 20 years. Tennis is my love. I enjoy bringing positive energy and memories for people who watch."

It was not all plain sailing for Djokovic, who offered up four break points, but the 34-year-old clawed back three of them.

"I was feeling excited and motivated," added Djokovic, who has progressed to the quarters in Dubai every time he has featured at the tournament.

"But also at the same time I was feeling stressed. Particularly at the moments when I was facing break points. I thought the atmosphere in the stadium was terrific."

Djokovic, who will lose his place at the top of the ATP rankings if Daniil Medvedev triumphs in Acapulco, should have little trouble in sealing a semi-final spot, though Vesely does come into that tie on the back of a surprise 6-2 6-4 win over world number 15 Roberto Bautista Agut, who had triumphed in Doha last week.

Murray falls short of landmark win

Second seed Andrey Rublev came from a set down to defeat Kwon Soon-woo 4-6 6-0 6-3, and will go up against American Mackenzie McDonald for a place in the last four.

There was no such joy for former world number one Andy Murray, however, who fell to Jannik Sinner 7-5 6-2.

"It is a special feeling [to share the court with Murray]," said Sinner, who will next face Hubert Hurkacz, a 6-3 6-2 winner over Alex Molcan.

"He is a legend. Winning three grand slams, many, many tournaments and he has had some unfortunate moments with surgeries. His fighting spirit is incredible.

Murray was chasing a 700th tour-level win of his career but failed to muster a single break opportunity against the Italian, who made it to the quarter-finals in Melbourne last month.

Alexander Zverev has apologised for his outburst at the Mexico Open that saw him "withdrawn" from the singles competition for attacking an umpire's chair. 

Zverev and Brazil's Marcelo Melo were in a super tie-break against Lloyd Glasspool and Harri Heliovaara when they were angered by a call made by the umpire, who overruled a decision from the line judge.

Glasspool and Heliovaara subsequently profited by delivering an ace on match point, which was followed by Zverev quickly walking off and smashing his racquet against the umpire's chair three times.

The world number three then shouted at the umpire that he had "destroyed the whole f****** match" before striking the chair again.

Zverev was due to be in second-round singles action against Peter Gojowczyk, but the ATP Tour confirmed the Olympic champion had been removed from the draw due to "unsportsmanlike conduct".

Former world number one Andy Murray condemned the 24-year-old's "reckless" outburst after his loss to Jannik Sinner, and Zverev has now apologised unreservedly for his raging response.

"It is difficult to put into words how much I regret my behaviour during and after the doubles match yesterday," Zverev wrote on Instagram on Wednesday. 

"I have privately apologised to the chair umpire because my outburst towards him was wrong and unacceptable, and I am only disappointed in myself. 

"It just should not have happened and there is no excuse. I would also like to apologise to my fans, the tournament, and the sport that I love.

"As you know, I leave everything on the court. Yesterday, I left too much. I am going to take the coming days to reflect – on my actions and how I can ensure that it will not happen again. I am sorry for letting you down."

Alexander Zverev has been "withdrawn" from the singles competition at the Mexican Open in Acapulco after attacking the umpire's chair at the end of his defeat in the doubles.

Zverev and Brazil's Marcelo Melo were in a super tie-break against Lloyd Glasspool and Harri Heliovaara when they were angered by a call made by the umpire.

A return on Melo's serve seemed to be called out by a line judge, but the umpire overruled the decision to put Glasspool and Heliovaara 9-6 up and give them match point, a subsequent ace ending the match in their favour.

As the pairs shook hands at the net afterwards, Zverev quickly walked off and smashed his racquet against the umpire's chair three times.

He then shouted at the umpire that he had "destroyed the whole f****** match" before striking the chair once more.

Zverev was due to face Peter Gojowczyk in the second round of the singles, but the ATP Tour confirmed the Olympic champion has been removed from the draw.

A brief statement read: "Due to unsportsmanlike conduct at the conclusion of his doubles match on Tuesday night, Alexander Zverev has been withdrawn from the tournament in Acapulco."

Rafael Nadal equalled the best start to a season in his career after winning his first match at the Mexican Open on Tuesday.

In his first match since a record 21st grand slam title in Australia, Nadal was a comfortable 6-3 6-2 winner over Denis Kudla, dropping only four points on serve.

Nadal is now 11-0 for the season, equalling the start he made in 2014, when his winning run was ended by Stan Wawrinka in the Australian Open final.

"I think I started playing well, a good victory in straight sets. That's always very positive for the confidence," said Nadal. "I think I played a very solid match for the first day.

"Of course, there are a couple of things that I can do better, but in general terms, I played well, so I can't complain at all."

Daniil Medvedev, who had also not played since the final in Melbourne, came through a tougher contest against Benoit Paire 6-3 6-4 in his opening match in Acapulco.

Medvedev held a two-set lead and looked in control before Nadal came roaring back to claim the Australian Open title, but the Russian could claim a landmark achievement in his first tournament since that heartbreak.

Medvedev, who faces Pablo Andujar next, will become world number one if he wins in Mexico, regardless of Novak Djokovic's performances in Dubai.

"It's always not easy to come back after some rest and some time off competition," he said. "I felt like my sensations were not at the top today, but I managed to fight until the end against a very tough opponent, and I'm happy that I managed to win."

Stefanos Tsitsipas racked up the 200th win of his career, holding off Laslo Djere to win two tie-breaks. He will now face J.J. Wolf, who surprised Lorenzo Sonego by fighting back from a set down to win 3-6 7-6 (9-7) 6-2.

Cameron Norrie was a straight-sets winner over Daniel Altmaier, while Yoshihito Nishioka battled through against veteran Feliciano Lopez.

Tommy Paul progressed after Matteo Berrettini retired when the American was poised to tie the match at one set all. John Millman also had to call an early halt to his match with Marcos Giron after a freak accident on court in which the Australian accidentally hit a ball into his eye.

At the Chile Open, home favourite Alejandro Tabilo beat Renzo Olivo in straight sets, while fifth seed Federico Coria was earlier knocked out by Yannick Hanfmann.

Miomir Kecmanovic defeated Marco Cecchinato, while there were also wins for seeds Sebastian Baez and Facundo Bagnis.

Jannik Sinner saved three match points to avoid a shock defeat to Alejandro Davidovich Fokina in the first round of the Dubai Tennis Championships.

After losing the first set, the world number 10 staved off defeat in a nerve-wracking second-set tie-break.

The fourth seed clung on as Davidovich Fokina saw a trio of opportunities to clinch a shock win go begging, the Spaniard made to pay as his Italian counterpart fought back to prevail 4-6 7-6 (8-6) 6-3.

Sinner, who will next face former world number one Andy Murray, said: "It was a very tough match. I know him, but we've never played against each other.

"It was the first time for both of us and it was a tricky one, saving three match points. On the first one I got lucky because it was out, but not so far [out]."

Second favourite Andrey Rublev won both the singles and doubles titles in Marseille last week and continued his fine form with a 6-4 7-5 win over Daniel Evans that saw the Russian send down 28 winners.

Sixth seed Denis Shapovalov had to recover from a set down to see off Marton Fucsovics, though fifth seed Hubert Hurkacz enjoyed a more routine straight-sets triumph over Alexander Bublik.

Eighth seed Roberto Bautista Agut made relatively light work of Arthur Rinderknech but defending champion and seventh seed Aslan Karatsev was stunned 7-5 6-3 by Mackenzie McDonald.

Karen Khachanov needed a little shy of three hours to beat Alex de Minaur, his dubious reward a second-round clash with Novak Djokovic as the world number one continues his return to the Tour following his controversial Australian Open absence.

Alexander Zverev saved two match points and battled back to salvage a dramatic victory over Jenson Brooksby at the Mexican Open in what was the latest finish in tennis history.

Second seed Zverev – the defending champion in Acapulco - wrapped up a dramatic win at 04:55 local time after his own lengthy contest had followed two other epic three-setters earlier on the schedule.

Zverev at one stage looked like he was on the way out but ultimately triumphed 3-6 7-6 (12-10) 6-2 to book a second-round tie against Peter Gojowczyk.

The German had beaten Brooksby in a match that also went to a decider when they clashed at Indian Wells in October and he was pushed to the limit again in a battle lasting 200 minutes.

Having dropped the first set, Zverev had to fend off three break points at 3-3 in the second and saved match points at 6-5 and 10-9 down as part of an epic tie-break that went in his favour. 

Zverev was then more comfortable as he broke twice in the decider to seal victory, his American opponent paying the price for converting just one of his seven break-point opportunities in a match that made history for its late finish.

The previous latest ATP finish time was Lleyton Hewitt's 2008 Australian Open clash with Marcos Baghdatis, which ended at 04:34 local time.

Elsewhere, Stefan Kozlov overcame cramps in the second set to outlast Bulgarian Grigor Dimitrov 7-6 (10-8) 5-7 6-3, with that match lasting three hours and 21 minutes.

John Isner sent down 29 aces and saved a match point as he trailed 5-2 in the third set, ultimately winning 7-5 6-7 (4-7) 7-6 (7-3) over veteran Fernando Verdasco in another epic topping the three-hour mark that helped to push back the start time for Zverev and Brooksby.

Seventh seed Taylor Fritz got past Frenchman Adrian Mannarino 6-3 6-3, while Dusan Lajovic knocked off Sebastian Korda 6-4 4-6 7-5 and eighth seed Pablo Carreno Busta beat Oscar Otte in straight sets.

At the Chile Open in Santiago, eighth seed Facundo Bagnis won 6-3 6-0 over Bernabe Zapata Miralles in the round of 32.

Brazilian Thiago Monteiro got past local Nicolas Jarry 7-6 (11-9) 6-4, while qualifier Juan Ignacio Londero and wildcard Thiago Seyboth Wild also progressed.

Alexander Zverev saved a match point and battled back to salvage a dramatic victory over Jenson Brooksby at the Mexican Open in what was the latest finish in tennis history.

Second seed Zverev – the defending champion in Acapulco - wrapped up a dramatic win at 04:55 local time after his own lengthy contest had followed two other epic three-setters earlier on the schedule.

Zverev at one stage looked like he was on the way out but ultimately triumphed 3-6 7-6 (12-10) 6-2 to book a second-round tie against Peter Gojowczyk.

The German had beaten Brooksby in a match that also went to a decider when they clashed at Indian Wells in October and he was pushed to the limit again in a battle lasting 200 minutes.

Having dropped the first set, Zverev had to fend off three break points at 3-3 in the second and saved a match point at 6-5 as part of an epic tie-break that went in his favour. 

Zverev was then more comfortable as he broke twice in the decider to seal victory, his American opponent paying the price for converting just one of his seven break-point opportunities in a match that made history for its late finish.

Elsewhere, Stefan Kozlov overcame cramps in the second set to outlast Bulgarian Grigor Dimitrov 7-6 (10-8) 5-7 6-3, with that match lasting three hours and 21 minutes.

John Isner sent down 29 aces and saved a match point as he trailed 5-2 in the third set, ultimately winning 7-5 6-7 (4-7) 7-6 (7-3) over veteran Fernando Verdasco in another epic topping the three-hour mark that helped to push back the start time for Zverev and Brooksby.

Seventh seed Taylor Fritz got past Frenchman Adrian Mannarino 6-3 6-3, while Dusan Lajovic knocked off Sebastian Korda 6-4 4-6 7-5 and eighth seed Pablo Carreno Busta beat Oscar Otte in straight sets.

At the Chile Open in Santiago, eighth seed Facundo Bagnis won 6-3 6-0 over Bernabe Zapata Miralles in the round of 32.

Brazilian Thiago Monteiro got past local Nicolas Jarry 7-6 (11-9) 6-4, while qualifier Juan Ignacio Londero and wildcard Thiago Seyboth Wild also progressed.

Novak Djokovic welcomed the "positive" reception he has received from his fellow players, after making his first appearance since missing the Australian Open.

Djokovic, whose decision not to be vaccinated against COVID-19 caused him to be deported from Australia on the eve of the year's first grand slam, eased to a 6-3 6-3 win over Lorenzo Musetti in just 74 minutes at the Dubai Tennis Championships.

Djokovic spoke publicly about his vaccination status for the first time in a BBC interview last week, while rival Andy Murray, who has spoken about his support for vaccination on numerous occasions, said that he "didn't like seeing" Djokovic's ordeal in Australia after his own win in Dubai.

Serbia's 20-time Grand Slam winner says that most of his fellow professionals have been supportive upon his return to action.

"So far here most of the players that I’ve seen – I haven’t seen too many players – but most of the players that I've seen have been positive and welcoming", he said after his round-of-32 win.

"It's nice to see, obviously. I can't say that was the case in Australia. It was a little bit strange. But here, it's gone well so far."

The 34-year-old impressed against Musetti, serving five aces, winning 71 per cent of his second serves (17 out of 24) and saving each of the seven break points he faced during his first outing of the year, and Djokovic was also pleased with the reception he received from the fans in Dubai, as well as with his performance. 

"I couldn't ask for a better reception," he added.

"It's been a while since I played, and I couldn't think of a better place to kick-start the season. Thank you for the reception and for welcoming me on court the way you did.

World number one Novak Djokovic has praised Rafael Nadal for his "incredible" triumph by winning last month's Australian Open after his own deportation forced him to miss the event.

Nadal moved beyond Djokovic with his record-breaking 21st Grand Slam title in Melbourne with a five-set victory over Daniil Medvedev in the final.

Djokovic was unable to compete in Melbourne due to his vaccination status, deported amid an ugly saga after arriving in Melbourne expecting to be permitted to play.

The Serbian, who returned to the ATP Tour on Monday with a 6-3 6-3 win over Lorenzo Musetti at the Dubai Tennis Championships, was gracious in praising Nadal, who had a nagging foot injury dog him late last year.

"I think it was four, five months ago that he was on the crutches and now he's winning a slam. It's incredible," Djokovic told reporters after beating Musetti.

"I've got tons of respect for him. I don't want to take anything away from his victory, me not participating in the tournament regardless."

The Serbian was pressed on missing the Australian Open and added: "Of course, it wasn't a pleasant feeling for me leaving the country the way I did and watching the tournament from far away."

Djokovic will play either Karen Khachanov or Alex de Minaur in the second round in Dubai, while Nadal is competing at the Mexican Open, with a match against Denis Kudla on Tuesday.

World number one Novak Djokovic has praised Rafael Nadal for his "incredible" triumph by winning last month's Australian Open after his own deportation forced him to miss the event.

Nadal moved beyond Djokovic with his record-breaking 21st Grand Slam title in Melbourne with a five-set victory over Daniil Medvedev in the final.

Djokovic was unable to compete in Melbourne due to his vaccination status, deported amid an ugly saga after arriving in Melbourne expecting to be permitted to play.

The Serbian, who returned to the ATP Tour on Monday with a 6-3 6-3 win over Lorenzo Musetti at the Dubai Tennis Championships, was gracious in praising Nadal, who had a nagging foot injury dog him late last year.

"I think it was four, five months ago that he was on the crutches and now he's winning a slam. It's incredible," Djokovic told reporters after beating Musetti.

"I've got tons of respect for him. I don't want to take anything away from his victory, me not participating in the tournament regardless."

The Serbian was pressed on missing the Australian Open and added: "Of course, it wasn't a pleasant feeling for me leaving the country the way I did and watching the tournament from far away."

Djokovic will play either Karen Khachanov or Alex de Minaur in the second round in Dubai, while Nadal is competing at the Mexican Open, with a match against Denis Kudla on Tuesday.

World number one Novak Djokovic has praised Rafael Nadal for his "incredible" triumph by winning last month's Australian Open after his own deportation forced him to miss the event.

Nadal moved beyond Djokovic with his record-breaking 21st Grand Slam title in Melbourne with a five-set victory over Daniil Medvedev in the final.

Djokovic was unable to compete in Melbourne due to his vaccination status, deported amid an ugly saga after arriving in Melbourne expecting to be permitted to play.

The Serbian, who returned to the ATP Tour on Monday with a 6-3 6-3 win over Lorenzo Musetti at the Dubai Tennis Championships, was gracious in praising Nadal, who had a nagging foot injury dog him late last year.

"I think it was four, five months ago that he was on the crutches and now he's winning a slam. It's incredible," Djokovic told reporters after beating Musetti.

"I've got tons of respect for him. I don't want to take anything away from his victory, me not participating in the tournament regardless."

The Serbian was pressed on missing the Australian Open and added: "Of course, it wasn't a pleasant feeling for me leaving the country the way I did and watching the tournament from far away."

Djokovic will play either Karen Khachanov or Alex de Minaur in the second round in Dubai, while Nadal is competing at the Mexican Open, with a match against Denis Kudla on Tuesday.

Former world number one Andy Murray did not like how Novak Djokovic was treated in Australia but says the 20-time major winner must live with the consequences of his decisions.

Murray and Djokovic both progressed through the first round at the Dubai Tennis Championships on Monday.

The Serbian's 6-3 6-3 win over Lorenzo Musetti marked his first on the ATP Tour in 2022, coming in the wake of his deportation from Australia due to his vaccination status ahead of the first major of the calendar year.

It remains unclear if Djokovic will be permitted to compete at this year's other majors - the French Open, Wimbledon and the US Open - given he remains unvaccinated.

"Like I said at the time, I don't agree with his decision. I think it would be a lot easier for him, obviously, if he was to get vaccinated," Murray told reporters after beating Australian Christopher O'Connell 6-7 (4-7) 6-3 7-5 in Dubai.

"But I also didn't like seeing him in the situation that he was in Australia as someone that I respect and have known since I was a child. I didn't like seeing that.

"There is consequences to the decisions he's made just now. He obviously has to accept that. But I don't think it's great for tennis if our best player is not competing in the major events."

Djokovic admitted after his win over Musetti that, as it stands, he cannot enter the United States to compete at next month's prestigious Indian Wells Masters, let alone the US Open.

The world number one added that he was hopeful the situation may change "in the next few weeks".

Novak Djokovic has said he cannot currently enter the United States, putting his participation in next month's Indian Wells Masters in doubt.

Djokovic won his first match back on the ATP Tour since missing the Australian Open on Monday, beating Lorenzo Musetti in the round of 32 at the Dubai Tennis Championships.

The men's world number one had not played a competitive match since early December and was last month deported from Australia on the eve of the Australian Open.

That decision was a result of Djokovic opting not to join the majority of his tennis peers in getting vaccinated against COVID-19 and amid controversy over how he handled getting the virus himself in December.

He showed no signs of rust as he eased to a 6-3 6-3 win over Musetti in just 74 minutes in his first match of 2022, hitting five aces, winning an impressive 71 per cent of his second serves (17 out of 24) and saving all seven break points he faced against his Italian opponent.

However, at a press conference following his victory, Djokovic admitted he is currently unable to enter the United States, and is therefore on course to miss March's prestigious Indian Wells Masters tournament.

"As of today, not. I can't go, I can't enter the United States," he said.

"As of today I'm not able to play. But let's see what happens. I mean, maybe things change in the next few weeks."

Djokovic has been included on the entry list for Indian Wells despite the tournament requiring all players are vaccinated against COVID-19.

Images of Djokovic do not appear in any of the tournament's build-up social media posts nor on the website's promotional announcement, while his entry-list inclusion was little more than a footnote – though did include him.

The statement read: "A power-packed line-up of ATP top-10 players will join [Rafael] Nadal in looking to put together a breakthrough performance in Tennis paradise.

"2021 US Open champion and 2022 Australian Open finalist Daniil Medvedev (world no. 2), 2021 ATP Finals winner Alexander Zverev (world no. 3), and 2021 French Open finalist Stefanos Tsitsipas (world no. 4) will each be in search of their maiden title in the desert.

"Reigning BNP Paribas Open champion Cameron Norrie (world no. 13) will look to replicate his extraordinary 2021 title run, in which he won his first Masters 1000 crown.

"World no. 1 and five-time Indian Wells champion Novak Djokovic is also on the tournament entry list."

Novak Djokovic won his first match back on the ATP Tour since missing the Australian Open, beating Lorenzo Musetti in the round of 32 at the Dubai Tennis Championships.

The men's world number one had not played a competitive match since early December and was last month deported from Australia on the eve of the Australian Open.

That decision was a result of Djokovic opting not to join the majority of his tennis peers in getting vaccinated against COVID-19 and amid controversy over how he handled getting the virus himself in December.

On Monday, he eased to a 6-3 6-3 win over Musetti in just 74 minutes in his first match of 2022, hitting five aces, winning an impressive 71 per cent of his second serves (17 out of 24) and saving all seven break points he faced against the Italian.

"All in all, it's a straight-sets win, so of course I have to be satisfied with my tennis, especially after not playing for two-and-a-half, three months," Djokovic said on court after the win.

"Of course, there were moments when I played great, there were moments when I made a couple of unforced errors in a row uncharacteristically. But it's normal to expect that [in my] first match after a while."

Djokovic will play the winner of Karen Khachanov against Alex de Minaur in the last 16.

Andy Murray is also through after a 6-7 (4-7) 6-3 7-5 win against Australian qualifier Christopher O'Connell. The Scot edged a tough match that lasted almost three hours, saving seven of eight break points faced. He will play either Alejandro Davidovich Fokina or Jannik Sinner next.

Elsewhere, Jiri Vesely overcame Marin Cilic 6-4 7-6 (7-3), while Filip Krajinovic beat Malek Jaziri 6-7 (4-7) 6-2 6-4 and Taro Daniel eliminated David Goffin after a 6-3 7-6 (7-5) win.

Rafael Nadal would "welcome" seeing Novak Djokovic play at future grand slam tournaments if he is granted permission to do so unvaccinated against COVID-19.

World number one Djokovic has courted controversy for his views on being jabbed and was last month deported from Australia on the eve of the Australian Open.

Djokovic has confirmed he is willing to miss future slams after stating he was prioritising his right to choose what to put into his body above his sporting ambitions.

In Djokovic's absence, Nadal became Australian Open champion and now has 21 titles – the most for a male player.

Nadal believes that any further omissions from Djokovic would only be harmful to the Serbian's chances of history not the slams themselves, but he would have no issue with his rival playing in the sport's biggest tournaments.

Speaking ahead of his return to the ATP Tour in Acapulco, Nadal said: "It will affect Novak's [grand slam] history if he can't play.

"It will affect him, not the grand slams themselves. Whoever wins the most slams – it will be what it will be. Everyone takes their own decisions and must live with them.

"In that sense, hopefully the pandemic subsides and we stop having so many deaths around the world and this horror ends, and we can return to normality – not for Novak but for the world in general.

"There are many people that have suffered, but if Novak can play the grand slams unvaccinated, then he is welcome."

Nadal defeated Daniil Medvedev in an epic Melbourne showpiece to become the first man to 21 slams, but he says the achievement has not changed his life.

"Absolutely nothing has changed having 21 slams, I won't lie to you," he added.

"From 20 to 21 there is not a very large difference. Life goes on exactly the same. The only thing that has changed is that now I play tennis, which a few months ago I couldn't.

"I am very happy for everything that happened in Australia, it was very unexpected, especially before the tournament started. In my life, nothing has changed. No title is going to change what is important in my life, which are other things.

"Already, at 35 years old, I have a lot of experiences behind me, of successes and bad moments and these sensations already help me to live in a more calm and different way."