The American tennis legend was a divisive figure during his playing career and sympathises with the 24-time Grand Slam champion for his failure to win over the crowds.

McEnroe told i news: "Rafa and Roger have legendary reputations, deservedly so. They've been incredible. Novak has not only equalled them but surpassed them in overall achievements, which seemed impossible.

"Both of those guys, Rafa and Roger, they are total class acts. They are loved and respected around the world. Novak gets the unfair treatment. He's the villain, the bad guy.

"I guess you need a good guy and a bad guy in a way. It can help the sport when you have rivalries like that.

"I think it's been unfair, honestly, because he is great for the game, on and off the court."

McEnroe has become a successful commentator and pundit since hanging up his racket and he explained that he wanted to have "fun" while offering his expert insight.

The seven-time major winner said: "My late great friend Vitas Gerulatis (a former Australian Open champion) did some commentary, way back when in the 80s, early 90s, before he tragically passed away.

"And I remember thinking to myself when I was still playing that if I ever did commentary, I wanted to be like him because he had fun doing it, which I think came across. Hopefully people feel that when I do it, that I'm enjoying this.

"I get to be at Wimbledon, how bad could it be? And (I get to) be like a backseat driver. 'Well, you should have done this!'

"The mike turned out to be a blessing in disguise for me, because I was able to show a side of my personality that I was pretty miserable at showing on the court; that I like to have some fun and can be hopefully a little bit funny at times, but then I knew the game. So I think that's the combination that works for me."