As Novak Djokovic tries to enter into the conversation of the greatest tennis player of all time, his coach, already has an opinion on the matter.

Andre Agassi backs Rafael Nadal over Roger Federer as the G.O.A.T. in men's tennis

Unfortunately for Djokovic, coach Boris Becker says the man his pupil conquered in the Wimbledon final has that distinction.

Even though Djokovic won the five-set thriller for his seventh Grand Slam victory, Federer's ability to force a fifth set added to his lore, Becker recently told stevegtennis.com.

"Roger Federer has already won Wimbledon seven times and has been World No. 1 for a very long time," Becker said. "He didn't really need another title, he is the greatest of all time and I have a lot of respect and admiration for him. With his comeback in the fourth set, he showed clearly why he deserves the (Greatest of All Time) status. He loves to compete, and he is a great ambassador for tennis. Kids should take as an example what he did in his career and how he managed to overcome complicated situations, as he did against Novak in the final in London."

U.S. Tennis could become extinct if a new player doesn't emerge soon to challenge for No. 1.

Federer has a record 17 Grand Slam championships, more than any other male tennis player. Rafael Nadal, thanks to nine French Open wins, is chasing Federer with 14. He is currently tied with Pete Sampras for No. 2.

But it was Sampras' rival, Andre Agassi, who already has proclaimed that Nadal is the G.O.A.T.

"I'd put Nadal No. 1, Federer No. 2," Agassi told Singapore's Straits Times newspaper.

"Federer separated himself from the field for four years. He separated himself from (Andy) Roddick and (Lleyton) Hewitt. Nadal had to deal with Federer, (Novak) Djokovic, (Andy) Murray in the golden age of tennis. He has done what he has done and he's not done yet."

Agassi's statement came prior to the French Open; it's unclear whether Federer's Wimbledon run had any bearing on Agassi's thought process, but if Federer can make another similar run at the U.S. Open, Agassi could be revisiting that position - unless he loses to Nadal in the final.

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