Defending champion Andrey Rublev was able to find another gear to get through his first-round match at the Dubai Tennis Championships on Monday, beating Filip Krajinovic 7-5 6-2.

The number two seed got off to a rocky start, finding himself 5-2 down in the first set before dramatically turning the tide, winning five straight games.

Rublev's first serve percentage improved from 49 to 58 in the second set as he stepped up his game against his Serbian opponent.

"Filip is one of my good friends, and we always have tough battles," Rublev said after his win. "So, today I was going on court thinking that it was going to be a really tough match, and when he started the way he did, I didn't know what to do because he was playing so good.

"Somehow I calmed myself and said 'OK, restart at the bottom and raise my level', and I started to play much, much better. I was able to turn the match around and finish the match in a good way."

He will face Alejandro Davidovich Fokina in the second round after the Spaniard took just 52 minutes to beat Malek Jaziri 6-2 6-0, converting all five of his break points as he strolled to victory.

Seventh seed Alexander Zverev had to come from behind to beat Jiri Lehecka 4-6 6-3 6-4, while Tallon Griekspoor set up a second-round clash with top seed Novak Djokovic after the Dutchman beat Constant Lestienne 6-4 3-6 6-2.

Andrey Rublev and Andy Murray battled to outlast their opponents at the Qatar Open, while Daniil Medvedev breezed into the quarter-finals.

Top seed Rublev, who won this tournament in 2020, responded to a first-set setback to rally to a 1-6 6-1 7-6 (8-6) win over Tallon Griekspoor on Wednesday.

The world number five was staring at a fourth opening-round defeat in five appearances this year but saved three match points en route to fighting back from 5-2 down in the decider.

Murray and fourth seed Alexander Zverev played out another three-set thriller in the Middle East, with the former world number one triumphing 7-6 (7-5) 2-6 7-5.

That clash lasted three hours and three minutes in another marathon match for Murray after defeating Italian Lorenzo Sonego in a final-set tie-break in the first round.

Medvedev (3) had no such difficulty in a comfortable 6-4 6-3 victory over world number 147 Liam Broady.

Second seed Felix Auger-Aliassime had to regain his composure during his debut in Doha, but ultimately prevailed 4-6 6-1 6-4 against Jason Kubler.

World number eight Auger-Aliassime had lost his only previous meeting with Kubler, and an upset was on the cards after the Canadian was broken in the third game and was unable to recover.

Yet he found his form with a blistering second set, reeling off five straight games to restore parity and keeping his cool in the decider.

That victory teed up a last-eight meeting with seventh seed Alejandro Davidovich Fokina, who downed Kwon Soon-woo 6-3 6-2.

Jiri Lehecka will meet favourite Rublev after beating Emil Ruusuvuori 6-2 7-6 (7-2), while Botic Van De Zandschulp was shocked by world number 170 Alexandre Muller in a straight-sets defeat.

Elsewhere at the Open 13 Provence, fifth seed Maxime Cressy fell to a surprise second-round elimination after a 6-7 (5-7) 6-4 6-3 loss to home favourite Benjamin Bonzi.

There was no such luck for the other Frenchmen in Marseille as Alexander Bublik eased past Gregoire Barrere, while Stan Wawrinka beat Richard Gasquet 4-6 7-5 6-2 to reach the last eight.

Andrey Rublev suffered a first-round defeat to Alex de Minaur on a bad day for the big names at the Rotterdam Open.

Second seed Rublev won this event two years ago but there will be no such run this time around after his 6-4 6-4 loss on Wednesday.

De Minaur broke the world number five early in each set and sealed the win at the first time of asking, moving to a 3-0 head-to-head record against Rublev on hard courts.

The Australian will face Maxime Cressy in the next round, who bounced back from his Open Sud de France final defeat by beating Tim van Rijthoven.

Jannik Sinner saw off Cressy in that Montpellier showdown and the Italian carried that form into this tournament, though he needed three sets to overcome Benjamin Bonzi.

Frenchman Bonzi forced a decider but Sinner regained his composure in the final set to prevail 6-2 3-6 6-1 and set up a heavyweight clash with top seed Stefanos Tsitsipas.

There was no such progress for Alexander Zverev, who joined Rublev in suffering an early exit.

The German came unstuck 4-6 6-3 6-4 to home favourite Tallon Griekspoor, whose four wins over top-20 opponents have all come in Rotterdam.

Stan Wawrinka, the champion in 2015 and runner-up four years later, will face the winner of that tie, after he beat Richard Gasquet 6-3 6-3 to reach the quarter-finals.

Holger Rune reached the semi-finals in Montpellier, and like Sinner the fourth seed progressed into round two, claiming a routine straight-sets victory over qualifier Constant Lestienne.

"It was tricky. It's a lot about finding the rhythm here in the beginning of the tournament and first match you have to really be on your toes, especially I played a qualifier today who already has two matches in his bag," Rune said.

"It made it more difficult, but I'm happy how I handled every situation today."

Hubert Hurkacz was another seed to fall out, with the world number 10 going down 7-6 (7-4) 7-6 (7-5) to Grigor Dimitrov.

Rotterdam Open top seed Stefanos Tsitsipas and defending champion Felix Auger-Aliassime were joined by Daniil Medvedev in progressing through their first-round ties.

Auger-Aliassime won his first Tour-level title at the event last year and went from strength to strength in 2022, winning another three singles trophies.

The world number eight, seeded third, started his title defence with a convincing 6-2 6-3 defeat of Italy's Lorenzo Sonego on Tuesday.

"Of course, I was hoping to win and get through, but 6-2, 6-3 is a great performance against a player that is tricky like he is... it's a great way to start the week," said Auger-Aliassime, who needed just 82 minutes to clinch victory and set up a last-16 meeting with qualifier Gregoire Barrere.

The Canadian is relishing his title defence, and feels he is a stronger competitor than this time last year in a warning shot to his rivals.

He added: "Last year was an amazing year, but this year is a different one. I think I'm a better player overall.

"Of course, the best thing I can do compared to last year is win again, so hopefully I can do that. The draw is really strong, but I'm confident if I can keep playing the way I did today I'll get my chances and then we'll see."

Auger-Aliassime might be the reigning champion, but world number three Tsitsipas is the favourite.

Emil Ruusuvuori was no match for Australian Open runner-up, who prevailed 7-5 6-1 and has a 13-1 record for the season.

"The process that you get to repeat these things over and over again, it gives you tremendous understanding of how things actually work," Tsitsipas said. 

"I think being able to get in these moments more and more often on the Tour helps you understand, makes you wiser when you're trying to deal with all these problems."

Tsitsipas, who could face Open Sud de France champion Jannik Sinner in the next round, ensured there would be no curse of the top seed in Rotterdam, where the favourite had lost their first match in two of the last three editions.

On both occasions (2020 and 2021), that was Medvedev, but the former world number one fought from a set down to beat Alejandro Davidovich Fokina 4-6 6-2 6-2.

World number 10 Hubert Hurkacz also had to battle against a Spaniard in the form of Roberto Bautista Agut. The fifth seed needed three hours to win 7-5 6-7 (7-9) 7-6 (7-4) and tee up an encounter with Grigor Dimitrov. 

Alexander Zverev defeated Soonwoo Kwon in straight sets to book his progress, while Gijs Brouwer got the better of Marc-Andrea Huesler.

Alexander Zverev will not face disciplinary action from the ATP following its investigation into allegations of domestic abuse against him.

The two-time ATP Finals winner became the subject of an investigation in October 2021 after claims the prior year by ex-partner Olya Sharypova.

The sport's governing body hired an external private investigation company to look into the allegations, which Zverev has denied.

Now, after it was deemed there was "insufficient evidence" to substantiate the claims, it has been confirmed the German will face no further action.

"Based on a lack of reliable evidence and eyewitness reports, in addition to conflicting statements by Sharypova, Zverev and other interviewees, the investigation was unable to substantiate the allegations of abuse," the ATP said.

While no action is to be taken, the ATP added it would reevaluate its decision "should new evidence come to light, or should any legal proceedings reveal violations of ATP rules".

Zverev, who reached the 2020 US Open final and won men's singles gold at the Tokyo 2020 Olympics, achieved a career-best peak of number two in the world rankings last season.

An ankle injury at the French Open against Rafael Nadal ended his campaign and he only made his return to competitive action earlier this month, with a second-round exit at the Australian Open.

He took further legal action against Sharypova last year, as well as an online publisher, after further allegations of abuse were made, while lending his support for a domestic violence policy to be introduced by the ATP.

Taylor Fritz and Alexander Zverev were sent packing from the Australian Open as wildcard Alexei Popyrin and lucky loser Michael Mmoh sprang major shocks.

Australian Popyrin said he was living a dream after beating the fancied Fritz in an epic second-round match lasting four hours and two minutes on John Cain Arena.

American Mmoh, whose mother has Australian citizenship, knocked out former world number two Zverev just moments later on Margaret Court Arena.

Their exits followed the shock defeat for second seed Casper Ruud earlier in the day, as Novak Djokovic's half of the draw lost a host of big names.

Wildcard Popyrin won 6-7 (4-7) 7-6 (7-2) 6-4 6-7 (6-8) 6-2 against American eighth seed Fritz, revelling in the chants of "Popy" from the crowd afterwards.

The 23-year-old was close to tears, his voice breaking, after reaching the third round of a grand slam for the fifth time.

"This win, it means so much to me," Popyrin said. "I had the toughest year last year, didn't win many matches. I've won as many matches this year as I won in the whole of last year, and it's only January.

"Pre-season I put my head down and worked as hard as I could. I don't want that feeling I had last year ever again.

"I wrote that down to myself in my head, and I'm going to keep working, I'm going to keep pushing, I'm going to keep trying to go all the way."

Addressing the crowd, Popyrin added: "I love this feeling. I want more of this feeling. I want you guys to have this feeling more. I love you guys so much, thank you."

He is coached by former top-20 star Xavier Malisse and felt the Belgian's influence against Fritz.

"I was playing four hours, and me and my coach were locked in, it was like two against one against Fritzy. We had the same thoughts all the time," Popyrin said. "This is the dream for me and I don't want to wake up at all."

Mmoh was beaten by Aleksandar Vukic in the final round of qualifying but received a call into the draw at the last minute, after a late withdrawal, allowing him to cancel a flight home.

The world number 109 will face fellow American JJ Wolf next, for a place in round four, having ousted 12th seed Zverev 6-7 (1-7) 6-4 6-3 6-2.

Mmoh's father, Tony, represented Nigeria and won a match at the Australian Open in 1988.

"Life is crazy," Mmoh said. "Right when you think everything is looking dim, everything is looking dark, there's light at the end of the tunnel.

"My week is proof of that. I could easily have been in the States, was ready to be in the States, had my bag packed, my flight booked, I was meant to leave yesterday morning. The fact I'm playing Margaret Court is insane.

"If you look at my box over there, there's about five to seven Aussies. I used to come every single Christmas to visit them, unfortunately my mum couldn't be here, I feel like I'm half Australian because of them and I love you guys. This is like my second home now so might as well make it a homecoming.

"It's the biggest win of my career hands down. Coming out I felt the nerves a little bit. I settled down at the end of the first, and at that point I told myself I shouldn't even be here. I told myself on match point if I get a chance just go for it, because I shouldn't even be here."

Alexander Zverev believes the Australian Open is already a success for him after his five-set victory against Juan Pablo Varillas on Tuesday.

It was the German's first win since his foot injury at the French Open in June during his semi-final against Rafael Nadal.

Zverev only returned to tour-level tennis in December at the United Cup, where he lost to Jiri Lehecka and Taylor Fritz.

He fell a set behind twice against the Peruvian lucky loser Varillas, before fighting back to win 4-6 6-1 5-7 7-6 (7-3) 6-4.

The world number 12 hit 69 winners and won 83 per cent of his first serve points in the contest, which lasted four hours and nine minutes.

"I am extremely happy because I missed this over the past seven months," Zverev said after his victory.

"This match alone pays off for all the hard work and suffering that I have had. To win in front of this kind of crowd again.

"I can't wait for the rest of the tournament. No matter what happens from now, the tournament is already a success for me."

Zverev will face the winner of Michael Mmoh or Laurent Lokoli in the second round, with their match suspended at two sets all on Tuesday due to rain.

Rafael Nadal has denied he has already decided to follow Roger Federer into retirement after this year's French Open.

The Spaniard wil turn 37 in June, and calling time on his career at the grand slam he has won a record 14 times might be the ideal way to sign off.

Making predictions for the season, Germany's Alexander Zverev told Eurosport: "Unfortunately, I think Rafa will retire at Roland Garros. I don't want it to happen, but I think he will have a great tournament, potentially win it and say goodbye."

That would mean Nadal joining his former great rival Federer in waving goodbye to a glorious career after the Swiss played for the last time at the Laver Cup in September. Nadal's tears that night in London pointed to a realisation his own time on tour was also nearing its end.

However, Nadal denies Zverev has been given any encouragement to throw out such a specific retirement suggestion, which was revealed ahead of the Australian Open.

Nadal is the defending champion in Melbourne, and he also took the Paris slam last year to reach 22 for his career, putting him one ahead of Novak Djokovic.

"I don't know what's going to happen in six months," Nadal said, quoted by Eurosport.

"I have a very good relationship with Zverev, but not enough to confess something like that to him.

"The reality is that I'm here to play tennis, try to have a great 2023, fight for everything that I have struggled throughout my career, and I don't think about my retirement.

“You think about it week after week because that's how you show me at every press conference. But I will answer the same every time you ask me."

Nadal has lost six of his last seven tour-level matches, suggesting he might struggle to make serious inroads in his title defence, which starts against Britain's Jack Draper on Monday.

Asked if he felt vulnerable, Nadal said: "Yeah, of course. Without a doubt. I have been losing more than usual, so that's part of the business.

"I think I am humble enough to accept that situation and just work with what I have today. I need to build again all this momentum. I need to build again this confidence with myself with victories. But it's true that I have been losing more than usual.

"I already have been here for three weeks, practising every day with the conditions, with the best players. That helps a lot in general terms.

"My situation, I don't know what can happen on Monday, but my personal feeling, without a doubt, is better now than three weeks ago, in general terms."

Rafael Nadal suffered his second defeat in as many matches after going down 3-6 6-1 7-5 against Alex de Minaur at the United Cup.

The 22-time grand slam champion, who was also beaten by Great Britain's Cameron Norrie in his opening match, is still seeking his first victory of the season with the Australian Open just around the corner.

Home favourite De Minaur delighted the Sydney crowd by recovering from a set and break down to claim his maiden win over the world number two.

"I think it's definitely up there [as one of my best wins]," he said. "It's one of those achievements that you have unlocked in your career.

"But also, it's a big win for myself, one that I really needed. I'm going to cherish and use, take all the confidence from this and be able to hopefully take it to have a good [Australian] summer."

Spain and Australia are unable to progress to the City Finals, but Nuria Parrizas Diaz levelled the Group D tie with a 6-1 6-3 victory over Maddison Inglis.

The USA, who required just two points against Germany to advance to the next stage, set up a showdown with Great Britain after Taylor Fritz and Madison Keys enjoyed straight-set successes over Alexander Zverev and Jule Niemeier respectively. 

Italy moved to the brink of joining them in the City Finals after taking a 2-0 lead over Norway. Lorenzo Musetti overcame Viktor Durasovic in straight sets, while Martina Trevisan edged out Malene Helgo in three.

Greece require one win from their final three matches against Belgium to also advance, Stefanos Tsitsipas hit 12 aces on the way to defeating David Goffin 6-3 6-2 to level the Group A showdown at 1-1.

Poland's winner-takes-all Group B clash with Switzerland is also finely poised at 1-1. World number one Iga Swiatek beat Belinda Bencic 6-3 7-6 (7-3), before Marc-Andrea Huesler's 6-3 6-2 victory against Daniel Michalski.

Alexander Zverev recognised his game remains below expectations after ending a six-month competitive absence, but the German is unconcerned as he continues his recovery.

The two-time ATP Finals winner suffered a serious ankle injury during the semi-finals of the French Open against Rafael Nadal, ruling him out of the rest of the 2022 season.

Though he has played in a number of exhibition matches since, Zverev only made his competitive return to action on Saturday at the United Cup in Sydney.

There, he suffered a 6-4 6-2 straight sets loss to the Czech Republic's Jiri Lehecka, though he was philosophical about his performance afterward.

"My tennis is far away from the level I want it to be," he said. "I think it is normal, not playing for seven months. There are things that are different than I'm used to.

"[Am I] concerned? Probably not. Physically, I'm not at the level that I have to be. This is not even a question. I'm getting tired a lot quicker than I did. I'm not as fast as I probably was.

"I don't think it will be a matter of tomorrow, [or] after tomorrow. It will be a few weeks until I'm back to the level I want to be."

Zverev, an Olympic gold medallist and US Open finalist, is anticipated to figure in next month's Australian Open, where he will be chasing a maiden grand slam trophy.

The German is focused on reaching full fitness rather than putting undue pressure on himself, though, adding: "I think it's tough to set expectations right now.

"It would be unrealistic and quite stupid for me to set the expectations towards winning or something like that.

"Of course, I want to win. Everybody wants to win. [But] for me, it's about getting back the form that I'm used to."

World number two Alexander Zverev has withdrawn from the US Open as he recovers from ankle surgery.

The German went under the knife after tearing all three of the lateral ligaments in his right ankle during his French Open semi-final against Rafael Nadal.

Zverev will not make his comeback at the final grand slam of the year in New York, as his withdrawal was announced on Monday.

The 25-year-old reached his only major final at Flushing Meadows two years ago, losing to Dominic Thiem.

Zverev stated after his operation that surgery was "the best choice" to ensure his ligaments heal properly and he could return to competition "as quickly as possible."

The US Open gets under way next Monday, with doubts remaining over whether Novak Djokovic will be able to play due to the 21-time grand slam champion opting against receiving a coronavirus vaccine.

Novak Djokovic has slipped to seventh in the ATP Tour rankings despite winning Wimbledon, where ranking points were stripped in this year's tournament.

Players from Russia and Belarus were banned from competing at the third major of the year due to the ongoing invasion of Ukraine.

The ATP and WTA retaliated by stripping ranking points from the event at the All England Club, where the likes of world number one Daniil Medvedev and Andrey Rublev did not feature.

Moscow-born Elena Rybakina, who switched to represent Kazakhstan four years ago, lifted the women's title in the singles competition, while Djokovic triumphed for a fourth straight time in the men's event.

Yet, Djokovic has lost 2,000 rankings points – the standard total awarded to a grand slam singles champion – after winning in SW19 last year, with no such rewards available on this occasion.

That meant the Serbian has dropped from third place to seventh, his lowest position since August 2018 when he fell to 10th.

Djokovic moved within just one major title of Rafael Nadal's record of 22 grand slams, and the Spaniard has jumped up one spot to third.

Medvedev and Alexander Zverev are unmoved as the respective top two after losing just 180 rankings points in the latest edition. Both missed Wimbledon, with the Russian banned and the German still injured.

Stefanos Tsitsipas, Casper Ruud and Carlos Alcaraz make up the top six after climbing a place each, while Rublev, Felix Auger-Aliassime and Jannik Sinner are the trio behind Djokovic.

Nick Kyrgios appeared in his maiden major final against Djokovic at Wimbledon as world number 40, the lowest-ranked grand slam male finalist since Marcos Baghdatis (54) at the Australian Open in 2006.

Just a day later Kyrgios has dropped five places to 45th in the rankings, losing 90 points from his third-round berth last year. If the ban was not imposed, the Australian would have broken into the top 20.

Cameron Norrie is another loser from the ranking points fallout. His run to the semi-finals at the London major would have seen him climb to eighth, but instead he has to settle for 11th.

Daniil Medvedev has replaced Novak Djokovic as world number one ahead of the start of Wimbledon, where the Russian is banned from featuring.

The ATP and WTA boards decided to remove ranking points from the third grand slam of the year, with Russian and Belarusian players not allowed to compete due to the invasion of Ukraine.

The 26-year-old Medvedev will miss out from the grass-court major, which starts on June 27, alongside Andrey Rublev, Aryna Sabalenka, Anastasia Pavlyuchenkova and Victoria Azarenka.

But that could aid Medvedev's cause at the end of the tournament as Djokovic is the defending champion and therefore would have more ranking points to lose.

Djokovic has dropped to third in the world rankings, with the injured Alexander Zverev – who made the French Open semi-finals before retiring against Rafael Nadal – in second.

That means it is the first time since November 2003 that none of Djokovic, Rafael Nadal, Roger Federer or Andy Murray have appeared in the top two rankings spots.

Medvedev, who lost in the final of the Rosmalen Grass Court Championship on Sunday, became the first player other than Djokovic, Nadal, Federer or Murray to top the men's rankings in 18 years when he replaced the Serb as number one in February.

Alexander Zverev is determined to "come back stronger than ever" after undergoing ankle surgery on Tuesday. 

Zverev tore all three lateral ligaments in his right ankle during the second set of his French Open semi-final against Rafael Nadal last week. 

The German is set to miss Wimbledon after his hopes of winning a first grand slam at Roland Garros came to a painful end. 

Zverev is ready to knuckle down with his rehabilitation after going under the knife in his homeland. 

Along with a picture of himself in his hospital bed giving the thumbs up, he posted on Instagram: "We all have our own journey in life. This is part of mine. 

"Next week I'll reach a career-high ranking of number two in the world, but this morning I had to undergo surgery. After further examination in Germany, we received confirmation that all three of the lateral ligaments in my right ankle were torn. 

"To return to competition as quickly as possible, to ensure all the ligaments heal properly, and to reclaim full stability in my ankle, surgery was the best choice. My rehab starts now and I'll do everything to come back stronger than ever! 

"I am continuing to receive so many messages and would like to thank everyone once again for supporting me during such a difficult time." 

Nadal went on to beat Casper Ruud in the final in Paris on Sunday to claim a record-extending 14th French Open title, taking his astonishing tally of grand slam triumphs to 22. 

Alexander Zverev is suspected to have suffered several torn ligaments during his French Open semi-final against Rafael Nadal on Friday.

The world number three's hopes of winning a first grand slam title at Roland Garros this year were ended when he rolled his ankle late in the second set on Court Philippe-Chatrier.

Zverev was taken off the court in a wheelchair after his tournament came to a painful end in Paris.

The German will surely miss Wimbledon as he awaits confirmation of the extent of the damage he sustained.

He posted on Instagram: "Hey guys! I am now on my way back home. Based on the first medical checks, it looks like I have torn several lateral ligaments in my right foot.

"I will be flying to Germany on Monday to make further examinations and to determine the best and quickest way for me to recover.

"I want to thank everyone all over the world for the kind messages that I have received since yesterday. Your support means a lot to me right now!

"I will try to keep you updated as much as possible on further developments. See you next time @rolandgarros."

Nadal will attempt to win a record-extending 14th French Open title when he faces Casper Ruud on Sunday.