Nick Kyrgios comment in US Open press conference sparks frenzy

John McEnroe has made the staggering statement that he wouldn't be surprised if Nick Kyrgios retires after the US Open.

Kyrgios sparked somewhat of a frenzy in his post-match press conference at the US Open on Sunday when he said he'd 'never have to play again' after the tournament.

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Speaking to reporters after his win over World No.1 Daniil Medvedev, the Aussie star opened up about his motivation to win his maiden grand slam title and his desire to return home to see his family.

"It's the last biggest tournament of the year," he said.

"We've got to try and just tough it out and keep pushing each other, keep being positive.

"Next week we're going home. But three more matches potentially, then we never have to play tennis again."

While the comment appeared tongue in cheek, some interpreted it as if Kyrgios was suggesting he will walk away from tennis after the US Open.

He made similar comments after his loss to Novak Djokovic in the Wimbledon final in July, admitting he wasn't sure if he would have had any motivation to keep playing if he had've won.

Addressing Kyrgios' comments on Eurosport on Monday, American great McEnroe said he wouldn't be the least bit surprised of Kyrgios retired at age 27 because we've seen it before with Ash Barty.

Barty shocked the tennis world earlier this year when she announced her retirement at age 25, just weeks after winning the Australian Open.

“Well I've got some bad news for you. Ash Barty [retired after winning a major], so it’s not impossible to think that he could do that," he said.

“We hope he won't do that because there’s a phrase, I think it’s worldwide - ‘better late than never’.

"That applies to Nick, because he wasn’t professional for a long time, he played a lot of matches where he wasn’t giving it his all, and now you see what he’s capable of when he does.

"And he trains and he’s in shape and the guy’s phenomenal.”

John McEnroe backs Nick Kyrgios to win US Open

McEnroe was in awe of the new focus that Kyrgios has showed this year having won 20 of his last 23 matches, saying the Aussie will win the US Open if he continues the kind of tennis he played against Medvedev.

“First of all, I’ve said this before, the guy has got one of the greatest serves in the history of tennis," the American said.

"The guy was serving at 70 per cent - I don’t think people realise that’s the highest on tour, how big he serves, how good his second serve is – now he is backing it up big time. If he plays like he did last night, he is going to win the tournament.

“The way Kyrgios is serving, I don’t care where you stand. If you stand well back, did you notice he started serving and volleying?

"The guy is a genius on the court, he doesn’t need a coach, he did an unbelievable job tactically. Medvedev was throwing a lot at him – I was saying Medvedev will play long rallies, test him physically and he’ll win most of those points. Guess what? He didn’t even win most of those [longer] points.

"When Kyrgios gets down on his opponent's serve he lets it go a little bit, paces himself, manages himself well but he’s also a lot fitter than he has ever been.

“Nick needs to be comfortable with the team that is around him. It’s a tough job sometimes being in Kyrgios’ box – he’s in such a great place mentally and it’s like 'he’s figured it out'.

"He’s 27, he’s coming into his prime. I like him, he moves the needle. I’m glad he turned it around and I am only sad he is not playing in the Laver Cup. We’re still begging.”

Kyrgios will play Karen Khachenov on Tuesday (Wednesday AEST) for a spot in the semi-finals.

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