Novak Djokovic expressed his gratitude at being part of Roger Federer's "beautiful" farewell to professional tennis but admitted to being left with mixed emotions over the retirement of his rival.
The Serbian was present at The O2 on Friday night to watch his Team Europe colleague bow out from competitive sport following a doubles defeat in the Laver Cup to Jack Sock and Frances Tiafoe.
Federer partnered up with Rafael Nadal - the other member of the 'big three' - for his last match but in keeping with the unique situation of the London event, Djokovic was one of the most vocal to provide support for two players who have usually been his biggest competitors.
An emotional goodbye to the pro game was afforded to Federer, who received a succession of ovations and had a retirement video package played on the big screen before singer Ellie Goulding produced a performance that left the Swiss star and Nadal in tears.
Djokovic, speaking after his singles' victory over Tiafoe on Saturday, said: "Well, I think we would all agree this was one of the most beautiful moments anyone has experienced live or on a tennis court worldwide. We all knew it would be an emotional farewell for Roger but I think we were all taken away by the moment.
"At the same time it is a mix of emotions. Sadness because one of the greatest athletes of all time is leaving the sport but on the other hand seeing him happy with the way it all played out, I was just very grateful and privileged to be alongside other Team World and Europe players to witness that.
"It was one of the most beautiful moments I have ever experienced in my life, for sure."
Federer had hinted in the hours after his 'last dance' that a potential farewell tour could be on the cards.
He had announced last week the doubles contest on night one of the Laver Cup, the Ryder Cup-style team competition he set up, would be his last on the ATP Tour but the door has been left open for more chances to see him on tennis courts around the world, just not in a professional capacity.
"I have no plans whatsoever like where, how, when," Federer said during a press conference that did not finish until after 2am on Saturday. "All I know is I would love to go and play places I have never played before or go say thank yous for years to come to all the people that have been so supportive of me.
"Because the hard part about the Laver Cup was that tickets were already sold out. You know, the people who maybe would have also loved to be here couldn't make it. Maybe there is another way down the stretch we can party all together."
Defeat on a comeback was finally admitted publicly by Federer last week after a succession of operations during the last two and a half years on his right knee proved unsuccessful.
It meant the final singles contest of his career occurred at Wimbledon last year, where he lost in the quarter-finals to Hubert Hurkacz, but he insisted retirement - which he settled on last month - was no longer a scary concept.
"I was able to remind myself always on the court again how wonderful this is," Federer said. "This is not the end, end, you know, life goes on. I'm healthy, I'm happy, everything's great and this is just a moment in time."