Olympic report

Tennis

Roger Federer is still rolling in his pursuit of his first Olympic singles medal. Federer beat American John Isner 6-4, 7-6 (5) on Thursday and will play No. 8-seeded Juan Martin del Potro in the semifinals. Serena Williams, another reigning Wimbledon champion who is seeking her first Olympic singles medal, advanced by beating Caroline Wozniacki of Denmark 6-0, 6-3. Williams’ opponent in the semifinals today will be top-seeded Victoria Azarenka, who beat Angelique Kerber 6-4, 7-5. Russians Maria Sharapova and Maria Kirilenko will meet in the other women’s semi. Novak Djokovic also advanced on the men’s side and next plays Britain’s Andy Murray.

Volleyball

Captain Clay Stanley scored 19 points and the U.S. men’s team defeated Brazil 3-1 in a preliminary-round rematch of the Beijing final. The 23-25, 27-25, 25-19, 25-17 victory extends the United States’ Olympic winning streak to 11 matches.

Cycling

Germany’s Miriam Welte and Kristina Vogel won the gold in sprint track cycling after the Chinese duo of Guo Shuang and Gong Jinjie was disqualified for a lane change in the final. The Chinese pair had finished a victory lap and was celebrating when the announcement was made. Britain broke its world record set earlier in the day to win its second straight gold medal in the men’s team sprint.

Beach volleyball

All four American teams – two in the men’s tournament and two in the women’s – finished the round-robin atop their pools.

Water polo

Tony Azevedo scored four goals and the U.S. men’s team beat Britain 13-7 to remain undefeated at the London Games. The Americans are on top of Group B with six points, one ahead of gold medal-favorite Serbia, with two preliminary stage matches to go. Serbia played to an 11-11 draw with Montenegro. The Serbs face the U.S. on Saturday.

Boxing

U.S. boxers are dropping out of the Olympic tournament at a rapid rate. The American skid reached seven straight bouts with narrow defeats for lightweight Jose Ramirez and middleweight Terrell Gausha. Only welterweight Errol Spence and flyweight Rau’shee Warren – who hasn’t fought yet – are still alive. Ramirez started slowly and never caught up in a 15-11 loss to Uzbekistan’s Fazliddin Gaibnazarov, while Gausha was locked in a tight one with Beijing bronze medalist Vijender Singh of India before dropping a 16-15 decision.

Rowing

The United States defended its title in the women’s 8, maintaining its six-year dominance of the high-profile event. The Americans won in a time of 6 minutes, 10.59 seconds. Canada finished a half-length behind in second and the Netherlands took the bronze. The U.S. hasn’t lost a competitive race in the women’s 8 since winning the world title in 2006.

Field hockey

One day after upsetting Argentina, the United States women lost 1-0 to Australia.