Roger Federer continues to set opponents straight at Wimbledon, reaches quarterfinals

“My theory is, they’re both the reason the other is still playing,” said Sports Illustrated’s Wertheim, a Tennis Channel analyst. “If Rafa’s knees gave in on him, I bet Federer would have retired by now. If Roger weren’t still here, I bet Nadal would be like, ‘Yeah, I’m done.’ I think they’re keeping each other in it. They’ve still got the other one in their sights.”