Roger Federer clinched the first singles medal of his career Friday when he won an Olympic marathon, taking the third set 19-17.
Federer outlasted Juan Martin del Potro of Argentina in the semifinals 3-6, 7-6 (5), 19-17 in 4 hours, 26 minutes. Federer converted only two of 13 break-point chances, the second coming in the next-to-last game.
A four-time Olympian, Federer clinched at least a silver. On Sunday he'll play in the final against No. 3 Andy Murray of Britain.
Murray clinched at least a silver medal by beating No. 2-seeded Novak Djokovic of Serbia 7-5, 7-5.
Murray held all 12 of his service games and broke once in each set. When he ripped his final shot at Djokovic's feet for a winner, the partisan Centre Court crowd responded with a roar.
In 2008, Federer and Swiss teammate Stanislas Wawrinka won the gold in doubles. But Federer had been 0 for 3 in Olympic singles, the biggest hole in a resume that includes a record 17 Grand Slam titles.
With the win, Murray earned a rematch against Federer, who won when they met on the same court in the Wimbledon final a month ago.
Djokovic will play Juan Martin del Potro on Sunday for the bronze. Djokovic won the bronze in 2008.
In doubles, Mike and Bob Bryan are assured of at least a silver medal at the Olympics.
The top-seeded American pair defeated Julien Benneteau and Richard Gasquet of France, 6-4, 6-4 in the semifinals of the men's doubles at Wimbledon on Friday.
The Bryans next play the winner of the other semifinal between David Ferrer and Feliciano Lopez of Spain and Michael Llodra and Jo-Wilfried Tsonga of France.
The Bryans won bronze in Beijing in 2008.
On the women's side, Maria Sharapova will play for gold in the Olympic tennis final.
The third-seeded Sharapova defeated Russian teammate Maria Kirilenko 6-2, 6-3 in the semifinals at Wimbledon on Friday. She hit a forehand drive volley past Kirilenko on match point.
On Saturday, Sharapova will play Wimbledon champion Serena Williams after beating Russian teammate Maria Kirilenko 6-2, 6-3 in the semifinals.
Sharapova has won four Grand Slam titles, including the French Open this year. She missed the Beijing Olympics in 2008 because of a shoulder injury.
Serena Williams clinched at least a silver medal Friday and earned a berth in the Olympic final when she beat No. 1-seeded Victoria Azarenka 6-1, 6-2.
Williams has lost only 16 games through five rounds and has won 12 consecutive matches this summer at the All England Club, including her fifth Wimbledon title a month ago.
She teamed with sister Venus to win the gold medal in doubles in 2000 and 2008. They had a chance to clinch at least a silver in a semifinal later in the day.
Williams has won 14 Grand Slam singles championships, the most of any active woman.
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