Manchester City manager Pep Guardiola says he is full of admiration for Rafael Nadal, Roger Federer and Novak Djokovic, calling them the “three geniuses” of tennis.

Nadal, 38, is retiring after next month’s Davis Cup finals in Malaga, bringing the curtain down on an incredible career in which he has won 22 Grand Slam titles – including 14 French Open crowns.

Before then, he will face familiar foe Djokovic for the last time on Saturday at the Six Kings Slam, live on Sky Sports.

Guardiola says he felt “a little bit sad” when Spanish compatriot Nadal announced his retirement, but the Premier League boss has paid tribute to the three legends who have dominated men’s singles tennis for two decades, collectively winning 66 Grand Slam titles.

“I think it happened because he saw that he cannot be or compete in the level that he had been for two decades, but I admire all of them, all three,” Guardiola told Sky Sports’ new One on One series and podcast.

“I admire the consistency of ‘The Big Three’ every single season being there and never giving up, coming back from the setbacks.

“I admire all of them, so for me they are three geniuses. I tried to learn a lot from their body language, how they behave in the bad moments, how strong they are mentally, and of course the talent and skill.

“I think all three will be missed – but still Novak Djokovic can enjoy it – but the three will be missed.”

Guardiola also explained how he would observe the greats of the game and see how they would overcome adversity.

He said: “I would always pay attention to the way tennis players look at the ball with their eyes and how they behave in certain moments. I also want to see how losers react in the next match.”

Guardiola has enjoyed plenty of heavyweight battles of his own, competing in the Premier League against the likes of Arsene Wenger, Jose Mourinho and Jurgen Klopp.

Like Djokovic still standing from an era of great tennis players, only Guardiola remains in the top flight from that illustrious collection of managers.

“When you are here nine years and then you become the oldest in football…Jurgen is tired, and when you don’t get results you change the manager, so it’s a simple answer for that – we won – otherwise I would not be here,” said the 53-year-old former Barcelona and Bayern Munich boss.

“Here you have to win. This is the only job where people are demanding desperately to sack you. It’s our profession so you have to accept it.”

Catch our new football series One on One on the Sky Sports Premier League You Tube channel and listen to the podcast – search One on One from Sky Sports.