Boris Becker created a stir when he proclaimed in his autobiography that Novak Djokovic and Roger Federer don't like each other.

The words from Djokovic's coach seemed to be validated during the tennis rivals' 43rd career match that took place in the round-robin portion of the ATP Finals, according to USA Today's For the Win.

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Federer routed Djokovic in a 77-minute match on Tuesday, prompting Djokovic to give what appeared to be an honest assessment of the beatdown.

"You have those days when you are not feeling your best, not even close to the best," the top-ranked Djokovic said. "Credit to Roger for mixing up the pace, giving me always a different ball. He used the slice and spin very wisely. He served very efficiently.

"I made a lot of, lot of unforced errors. I just handed him the win, especially in the second set.

"He tactically played well. Undoubtedly, he was the better player on the court. But I think I also allowed him to play and penetrate through the ball and dictate the tempo from the baseline."

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It was that second sentence that riled up No. 3-ranked Federer, who took a 22-21 advantage in their head-to-head series.

"He handed [me] the win? Well, he wasn't as good as in the first set. But I feel, honestly, with the way he's played this season, you still have to put him away.

"It's not an easy thing to do. It's not like he played terrible. I know he can play better. Why did he play that way? I'd like to give myself credit for that, quite honestly, yeah."

Becker said Federer and Djokovic had issues, another For the Win report indicated, but that Federer was too worried about his image to let his feelings be known.

Federer clinched a spot in the semifinals, while Djokovic now must beat Tomas Berdych to advance. The two could meet again in the championship match -- which Federer says still features Djokovic as the favorite, according to tennis.com.

"It's always good beating Novak or any top player moving forward," Federer said. But still to me, Novak is still the favorite of the tournament."

The question is, did Federer say that to mock Djokovic, whom he just beat in straight sets?

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