Roger Federer has admitted to changing his opinion on both Novak Djokovic and Rafael Nadal after retiring. The trio dominated the last two decades of men’s tennis.

Only Djokovic, 37, is still going strong after Federer, 43, called time on his career in 2022 and Nadal, 38, followed suit last week. Nowadays there’s plenty of mutual respect between all three.

But that wasn’t always the case with Federer, who admitted to getting swept up in their intense rivalries during his playing days. He and Nadal first battled one another in the mid-2000s, when they were very much foes and not friends.

Explaining how their relationship developed over time, Federer said last year: “We started respecting the rivalry. We almost miss it, playing each other every weekend. Back in the day we couldn’t stand each other probably for that.

“Obviously it was intense but always good and we always got along well, not just the two of us but also our teams, my parents and his parents, my coaches and his coaches, his sister and my sister – like the whole surroundings were very respectful and very good.

“Then as we got older and we knew maybe time was ticking and we’re about to not see each other so much – I had family, that changes someone anyway – we started to talk about all different things in life. More on injuries, more on kids as he is also a father now. The conversations change and in the process we also respect the rivalry that we used to have.”

Djokovic, meanwhile, burst onto the scene with his first Grand Slam victory at the 2008 Australian Open. Federer had first played him in 2006, winning 6-3, 2-6, 6-3 in a clash in Monaco.

Recalling what his initial assessment of the Serb was, he explained on his Amazon Prime documentary Federer: Twelve Final Days: “I walked off the court and thought, ‘Yeah, he’s OK’.

“Even though there was some hype around him, I wasn’t really fully convinced. I think I didn’t give Novak the respect he deserved because of his technical flaws.

“I felt like Novak had a very extreme forehand grip and his backhand for me wasn’t as fluid as it is nowadays. But then he ironed those things out super well and became an unbelievable monster of a player.

“I guess he was the party crasher of Rafa and Roger fans. There was a lot of Rafa-Roger love there. so when Novak came probably a lot of people said, ‘Look, we don’t need a third guy. We’re happy with Roger and Rafa’.”

Djokovic has gone on to surpass Federer (20) and Nadal (22) with 24 Grand Slam titles to his name. But the debate about who is the greatest of all time rages on regardless.