Andy Murray of Britain will meet Roger Federer in the Olympic men's singles final on Sunday after a straight-sets win over Novak Djokovic of Serbia.
Murray beat the world number two 7-5 7-5 on the centre court at Wimbledon and is now guaranteed at least a silver medal.
''The court was going nuts at the end and it was so loud,'' said Murray afterwards. ''I haven't experienced noise like that on a tennis court (before).''
Federer took four hours 26 minutes to beat Juan Martin del Potro of Argentina 3-6 7-6 (7-5) 19-17 windy conditions.
Federer previously beat Murray at the All England Club final on 8 July.
In the women's singles, Serena Williams, beat Victoria Azarenka of Belarus 6-1 6-2 in 63 minutes.
She will meet Maria Sharapova in the final on Saturday.
Sharapova beat Maria Kirilenko in an all-Russian semi-final, 6-2 6-3.