Fifth seed Jennifer Capriati set up a Rome Masters final against Amelie Mauresmo when she stunned top seed Serena Williams 6-4, 6-4 on Saturday.
Sunday's final will give the American a chance to gain revenge for her 6-2, 6-0 semi-final loss against the Frenchwoman in Berlin last week.
Capriati had last beaten Williams nearly three years ago, in the quarter-finals of Wimbledon.
Since then Williams has defeated her on eight occasions, including a Rome semi-final two years ago on her way to winning the title.
Williams looked more comfortable in the early stages of the match, losing just three points in her opening four service games, while forcing Capriati to fend off three break points.
The balance swung in the ninth game, however, when a long forehand and a double fault gave Capriati two break points. She converted the second with a whipped crosscourt winner before serving out the set.
Williams regrouped to hold serve in the opening game of the second set, but aggressive returning and heavy groundstrokes pressured her into a series of errors as Capriati broke in the third and fifth games.
Serving at 5-2, a nervy Capriati double faulted on match point to allow Williams to grab a break back, but she steadied herself in her next service game, holding off two more break points to close out the match.
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"I think the little difference was that she made a few more mistakes than usual and starting playing better too late in the match," said Capriati afterwards, explaining how she had broken her long losing streak against Williams.
"Other matches against her have been like this. I've led 5-1 or 5-2 and then let it slip away. Today I just tried to stay concentrated to the end and not get negative."
Her opponent in the final, Amelie Mauresmo had a much smoother passage past eighth seed Vera Zvonareva 6-2, 6-3.
Mauresmo had worked hard to defeat quarter-final opponent Silvia Farina Elia in a rain-interrupted three-setter on Friday, but looked fresher than the Russian who failed to hold serve once in an error-strewn first set that lasted just 28 minutes.
Mauresmo hit her rhythm early in the second, serving strongly and hitting deep to take a 4-1 lead.
Zvonareva briefly threatened to haul herself back into contention in the seventh game, when a pair of forehand errors allowed her to break back, but Mauresmo rallied to restore her one-break advantage and serve out the match.
"I'm very satisfied with the way I played today. I was in control from the beginning. I knew she was a strong, determined player, so I had to be concentrated from the start," she said.
"Maybe tomorrow I'll finally win it. I'll certainly be watching the next match very closely, but whatever happens tomorrow it will be great preparation for Roland Garros."
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