Federer Shakes Off Hot Roddick at US Open

"There was so much good serving that it's hard to say it was great, great tennis," Federer said. "But I thought it was a high level. You couldn't allow yourself to make any easy mistakes because they would be costly."

Roddick said he was happy with giving it his best against the Swiss.

"I played my ass off out there tonight. I played the right way. So, you know, it helps, but that doesn't mean I can't be pissed off...If I feel sorry for myself I'm a real asshole," Roddick said. "Honestly, I get to play in atmospheres like that. You know, I get a lot of opportunities. I'm very lucky. If I start feeling sorry for myself I need a serious sense of perspective."

In the semifinals Federer will face No. 4 seed Nikolay Davydenko, who on Wednesday ground down No. 10 seed Tommy Haas 6-3, 6-3, 6-4.

Davydenko has yet to lose a set in the tournament, and after the match said something to the effect that it's a good thing.

"If you win everything in three sets, yes, you feeling also tired, because mentally not so tired and physically also because you have always day off and you recovery for the next game," Davydenko said. "I don't know, like [Novak] Djokovic recovery every four hours, play five sets or four sets, and, you know play four or something, like five hours. It's interesting. But for me if I play less hours is good for me."

On tap Thursday at the US Open are the remaining quarterfinals in (20) Juan Ignacio Chela vs. (15) David Ferrer, and (17) Carlos Moya vs. (3) Novak Djokovic.