Swiss world number one Roger Federer lost to American eighth seed James Blake in the men's singles quarterfinals of the Olympic tennis event on Thursday.

Roger Federer of Switzerland hits a return against James Blake of the United States during the men's singles quarterfinal of the Beijing 2008 Olympic Games tennis event at the Beijing Olympic Green Tennis Court in Beijing, China, Aug. 14, 2008. Blake won the match 2-0. [Wang Yuguo/Xinhua]

In a match delayed by rain for three hours, Federer was playing below standard, slumping at 6-4, 7-6(2) in just one hour and 30 minutes.

"I'm speechless. This is unbelievable. It's not very often you get to say you beat the No. 1 player in the world anytime, but to do it at the Olympics with USA on your chest, I'm so proud to be a part of this team," said Blake.

"I'm inspired by other great athletes on the tennis team and in every team from swimming, track and field, everyone that's inspired me here has gotten me through this win.

"I proved tonight that I played with the best tonight and it couldn't have happened to me on a better stage."

It was the American's first win over the Swiss. Federer entered the match with an 8-0 record in matches against his opponent and had only ever lost one set to Blake.

Federer had already looked shaky in the opening set, making more unforced errors and was totally outclassed by the American in baseline and serve.

Both players held serve in the first nine games of the opening set, but a long forehand from Federer gave Blake a break point with the Swiss serving at 4-5. Blake converted on it to draw the first blood after Federer drove the ball into the net.

In the second set, Federer had no signs of recovery, being broken in his first service game. Despite breaking back in Blake's next serve, Federer still handed the set and the whole match after losing the tie- break at 7-2.

"Maybe if you play him enough times he's bound to have an off day. He didn't play his best today, but I felt like I served well when I needed to, especially in that tiebreaker. If I can just come through on those big points," said Blake.

"In a lot of the other matches, it's been a point here or a point there and that's why he was No. 1 in the world because he played those points better than everyone, today I played them well."

Federer made 56 unforced errors to Blake's 38 in the match.

"I have more work to do (in winning the Olympic medal). The fourth position will be tough because you're in position and you just have to win one out of two matches. But the four guys who are left are going to be tough, there aren't going to be any easy matches. I know I'm going to have to be focused and get a good night's sleep and be ready for tomorrow."

The American will face either No. 12 seed Fernando Gonzalez from Chile or Frenchman Paul-Henri Mathieu in the semifinals.

(Xinhua News Agency August 14, 2008)