BEIJING - Roger Federer's bid for his first Olympic singles medal has ended with a loss to American James Blake. With the sort of lackluster performance that was once unthinkable for Federer, he was eliminated in the quarterfinals on Thursday night. Meanwhile, Serena and Venus Williams both lost as well.
The Federer upset was a stunner in that Blake had won only a single set in their previous eight matches. But the top-seeded Federer is battling a yearlong slump that has left him stalled at 12 major titles, two shy of Pete Sampras' record.
Federer's latest defeat means no rematch in Sunday's final against Nadal, who won in epic fashion when they met for the Wimbledon title.
Serena Williams lost her quarterfinal match at the Olympics to Elena Dementieva of Russia.
Dementieva, who won a Silver in Sydney in 2000, beat Williams 3-6, 6-4, 6-3 in their singles match Thursday night.
Williams now pins her medal hopes on doubles. She was to play a second-round doubles match later with sister Venus. They won gold in doubles in Sydney.
The fourth-seeded Serena tried to rally from a 5-0 deficit in the final set against the No. 5-seeded Dementieva.
Williams overcame two match points during an 18-point game to hold for 5-3. But Dementieva held at love in the next game, sealing the victory when Williams pushed a volley wide.
Venus Williams was another upset victim in Olympic tennis, losing to Li Na of China in the quarterfinals.
Williams, who won gold medals in singles and doubles at the 2000 Games, was beaten 7-5, 7-5. She followed to the sideline her sister Serena and top-seeded Roger Federer, who both lost earlier Thursday.
A wayward forehand plagued Williams, and she sent one long to lose serve and fall behind 6-5 in the second set. The reigning Wimbledon champion had three more forehand errors in the final game, and when Li hit a service winner on match point, the crowd responded with the biggest roar of the tournament.
Williams remained in the doubles competition and was to play with her sister in the quarterfinals later Thursday.