Roger Federer is regarded by many as the greatest tennis player ever and is a national hero in Switzerland.
Novak Djokovic has offered financial support and any other help required to Ukrainian former world number 31 Sergiy Stakhovsky, who has enlisted in his country's reserve army amid Russia's invasion of its neighbour.
Djokovic left little doubt that he would also be there trying to win major number 23.
The ATP said that penalties and fines would apply for abuse or misuse of the coaching conditions and that the trial will be assessed at the end of the 2022 season for potential inclusion in future.
Roger Federer on Sunday congratulated Serbia's Novak Djokovic on joining the 20 Club.
Roger Federer will miss the Australian Open in January and is unlikely to return to competition until mid-2022 as he recovers from multiple knee surgeries, the former world number one told Swiss media.
The ravages of two decades on tour mean Rafael Nadal has rarely been able to prepare for majors like other players, forcing him to rely on skills and mental fortitude.
Novak Djokovic beat Daniil Medvedev in the US Open final to win a 24th Grand Slam singles title and equal Margaret Court's record haul.
Federer's preparations for the claycourt Grand Slam were cut short in Geneva
Roger Federer said he has never faced problems in switching from claycourts to grass and hopes his decision to play on his least favourite surface at Roland Garros will prove beneficial to his Wimbledon bid.
Federer, 39, was pushed to the limit in his first match back on Wednesday when he beat Briton Dan Evans in three sets but the Swiss looked well in control in the opening set against the unseeded Basilashvili.
'His expression was like a million dollars!'
Factbox on Novak Djokovic's five Wimbledon titles
The 190th-ranked Indian stretched 20-time Grand Slam Champion Roger Federer to four sets in opening round of the US Open.
Summary of sports events and persons who made news on Saturday.
'I still feel my body is serving me, is listening to me well. That's the key I think when you get to 35-plus.'
Second seed Novak Djokovic outclassed Roger Federer in straight sets to enter the final of Australian Open in Melbourne on Thursday. Seven-time champion Djokovic started off slowly before he took complete control to register an emphatic 7-6, 6-4, 6-3 victory in the first semi-final.
Rafael Nadal is the oldest title winner in the history of the clay-court tournament.
'The last few games obviously... you can feel that you're not coming back from it. I'm not used to that kind of situation, especially not here.'
Spaniard Rafael Nadal will team up with perennial rival Roger Federer for the third edition of the Laver Cup in Geneva next year.
In the clash of legends, Roger Federer got the better of Serena Williams in their historic clash in the mixed doubles at the Hopman Cup in Perth on Tuesday.
It was Roger Federer's fastest defeat since losing to Franco Squillari in 54 minutes in Sydney in 2003.
Novak Djokovic has so far declined to disclose whether he is vaccinated and his father told Serbia's TV Prva that governing body Tennis Australia's stance on players being vaccinated was tantamount to "blackmail".
Nadal will not be playing at Wimbledon, having decided to rest, while eight-time champion Federer is showing signs that, at 39, the window of opportunity to win one more Slam is closing.
The Swiss was handed a code violation for swearing in the third set of Tuesday's match after the lineswoman reported Federer to Serbian chair umpire Marijana Veljovic.
The two great rivals meet at Roland Garros for the first time in eight years in Friday's tie.
A quick look at Rafael Nadal's domination of Roger Federer at Roland Garros.
Federer had his first hit on Thursday at the ATP 500 event at the German city of Halle, where he has won 10 titles.
All players who want a visa to compete in the Australian Open will need to be fully vaccinated for COVID-19, the country's immigration minister said on Wednesday, putting Novak Djokovic's title defence and Grand Slam record bid in doubt.
The 20-time Grand Slam champion smoothly pressed the accelerator to take the tiebreak and outclassed Cilic in the fourth set to claim a 6-2, 2-6, 7-6 (4), 6-2 win.
World number one Rafael Nadal has been drawn alongside defending champion Alexander Zverev, Association of Tennis Professionals (ATP) reported.
Images from the Wimbledon semi-final played between Roger Federer and Rafael Nadal on Friday
Roger Federer will make his return to the tennis circuit from a double knee surgery at an ATP 250 tournament in Qatar in March, having not played since last year's Australian Open.
Djokovic has refused to take the vaccine and appears set to miss out on the year's last Grand Slam
Roger Federer has revealed he underwent knee surgery and will be out of action until the summer.
Fritz delivers as US win inaugural United Cup crown
'Let's be confident, let's be positive and let's see what's going on'
Nadal arrived in Paris with his own doctor to get through the tournament despite the injury.
Be it cheering for Roger Federer or Garbine Muguruza at the Wimbledon final, the Hollywood brigade made their presence felt at both, the women's and men's final at Wimbledon over the weekend. We caught a few cine stars watching their tennis heroes in action at the All England Club...
The 'Big Three' of men's tennis have found some "fresh energy" to thwart the charge of younger players on the tour, world number one Novak Djokovic said after setting up yet another title clash against his biggest rival against Rafael Nadal.