'He's that good': Roger Federer's stunning Rafael Nadal admission

It’s a debate that has raged among tennis fans for some time, and likely will for years to come.

Who will go down as the greatest of all time - Roger Federer or Rafael Nadal?

In all likelihood, it’ll be too difficult to make a definitive judgement until both have retired. That doesn’t look like it’ll happen any time soon.

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In the meantime though, one of the duo has made a stunning call as to who will be remembered as the best ever.

In an interview with Argentinian sports broadcaster TyC Sports, Federer said he believed Nadal would boast a better record when their illustrious careers were over and done with.

Prompted by the interviewer, who revealed quotes from tennis legends Bjorn Borg and Pete Sampras predicting Federer would achieve GOAT status, the Swiss star looked instead to his Spanish rival Nadal.

“I admire those players so much. I’m humbled to be considered part of the best ever that some even consider me the best,” Federer said.

“Good guy, great player, my God — who would have thought that (Nadal) was going to be world No. 1 again this year after being world No. 1 for the first time 11 years ago.

“All the people were saying that he was going to be injured, that he was going to not make it, that he was not going to be healthy at one point, his game is too brutal, but he found a way and he has had another incredible season with two Grand Slam wins this year.

“I am happy that we had the matches and the battles that we had particularly at Wimbledon, French Open, even in Australia, we have had some massive matches.

“He is going to go down as maybe the greatest player of all time, he’s that good of course.”

As for his own retirement? Don’t hold your breath, Federer says.

In an interview with the TODAY show in the US, Federer said while the thought had crossed his mind, he insisted he would play for as long as he could.

“I’ve been asked all week about how retirement is going to be and when it is going to come, I think they all needed to know,” Federer said.

“But no, this is not about retirement. On (the company) doesn’t want me to retire, they want me to play as long as possible and that is my goal. I will never retire!”