Following are the results from the Beijing Olympic tennis event on Thursday (prefix number denotes seeding):

Men's singles quarterfinals:

8-James Blake, United States, bt 1-Roger Federer, Switzerland, 6-4, 7-6(2)

Men's doubles quarterfinals:

Simon Aspelin/Thomas Johansson, Sweden, bt Mariusz Fyrstenberg/Marcin Matkowski, Poland, 7-6(5), 6-4

Women's singles quarterfinals:

5-Elena Dementieva, Russia, bt 4-Serena Williams, United States, 3-6, 6-4, 6-3

9-Vera Zvonareva, Russia, bt Sybille Bammer, Austria, 6-3, 3-6, 6-3

(Xinhua News Agency August 14, 2008)