Beijing:Spain's Rafael Nadal underlined his dominance of men's tennis with a three-set win over Novak Djokovic to reach the Olympic Games final on Friday.
Nadal, who will face Chile's Fernando Gonzalez on Sunday, overcame a second-set lapse to win 6-4, 1-6, 6-4 in two hours and 10 minutes.
A horrendous error from the third-ranked Djokovic sealed it for Nadal when the Serb missed the open court with an overhead on match point.
Nadal, who becomes world number one the day after the final, is now just one match away from adding the gold medal to this season's seven-trophy haul including the French Open and Wimbledon.
The high-energy 22-year-old started with a bang, breaking at 1-0 and again at 3-1, before Djokovic picked up the pace.
He struck again in the decider when Djokovic was serving to stay in the match, returning the Serb's hardest forehand and retrieving a drop shot. Djokovic fired his smash wide on the second match point.
Earlier a blazing row overshadowed the other semi as beaten American James Blake accused Gonzalez of lacking sportsmanship.
In the women's draw, Russian sixth seed Dinara Safina won 6-2, 5-7, 6-3 to hand Jelena Jankovic her first defeat as world number one.
And Simon Aspelin and Thomas Johansson won a marathon 59-game doubles match -- the longest men's three-setter in Olympic history.
Blake and Gonzalez's semi-final was not much shorter at 42 games, and bitter controversy erupted after the 2004 bronze-medallist's 4-6, 7-5, 11-9 win.
US number one Blake, who stunned top seed Roger Federer in the quarters, claimed the Chilean touched a ball which went out but didn't admit it to the umpire.
Blake said he had lost "a little faith" in the 2004 bronze medallist and doubles champion over the incident, which happened at a crucial moment in the deciding set.
"Playing in the Olympics, in what's supposed to be considered a gentleman's sport, that's a time to call it on yourself. Fernando looked me square in the eye and didn't call it," Blake said.
"That's a disappointing way to exit the tournament when you not only lose the match, but you lose a little faith in your fellow competitor," he added.
Gonzalez, who saved three match points, denied any wrongdoing and said if he was sure he touched the ball, he would have said so.
"If I'm hundred percent sure about it, I will give it. But I'm not sure," he said.
Safina will meet China's Li Na in the women's semi-finals while Vera Zvonareva and Elena Dementieva go into an all-Russian clash.
Jankovic was pleased with her run to the quarter-finals despite being plagued by a calf injury.
"You cannot expect miracles to happen when you have some problem. I've been taking injections before I went on court just to be able to perform, otherwise I couldn't play," she said.
Meanwhile, Aspelin and Johansson beat Arnaud Clement and Michael Llodra of France in the longest three-set men's match in Olympic history.
The eventual scoreline of 7-6 (8/6), 4-6, 19-17, played over four hours and 46 minutes, added up to 59 games plus a tie-break, beating the previous record of 53 games.
Federer and Stanislas Wawrinka upset top seeds Bob and Mike Bryan to reach the final, assuring the 12-time Grand Slam winner of his first Olympic medal.
Ukraine's Alona Bondarenko and Kateryna Bondarenko reached the doubles semis with a 6-1, 3-6, 7-5 win over Italians Flavia Pennetta and Francesca Schiavone.