By Michelle Kaufman

McClatchy Newspapers

BEIJING The What’s-Wrong-With-Roger Federer questions will continue after he was stunned in straight sets in the Olympic quarterfinals by James Blake of the United States, who was 0-8 against Federer before Thursday.

Blake kissed the American flag on his shirt after knocking off a frustrated Federer 6-4, 7-6 (7-2) in a match delayed nearly four hours by rain.

Federer was hoping for a good weekend at the Olympics to lessen the sting of losing his four-year hold on No. 1 when the new rankings are released Monday. Spaniard Rafael Nadal will take over the tennis throne after a spectacular three months in which he beat Federer in the finals at the French Open and Wimbledon, and won five tournaments.

Federer was determined to turn things around with an Olympic medal after going home empty handed in 2000 and 2004. Instead, he heads home with more questions.