Amélie Mauresmo will meet the second-seeded Kim Clijsters of Belgium in the final of the Italian Open after defeating the American World No 1, Serena Williams, in a hard-fought semi-final.
Clijsters cruised to an easy 6-3 6-2 victory over the 13th seed, Ai Sugiyama of Japan, in this $1.3m event, a key clay-court tune-up for the French Open, which is little more than a week away.
Serena Williams lost her second match of the year when falling in three sets to Mauresmo, whose 1-6 7-5 6-3 victory was marked by a sharp mid-match turnaround.
Williams, the defending champion in Rome and Paris, was within two points of closing out the match on her serve when she was ahead 5-4 in the second set. But a difficult backhand volley miss by Williams gave Mauresmo a break to get back on serve, and the Frenchwoman went on to win three straight games and stretch the match into a deciding third set.
After trading breaks early in the final set, Mauresmo broke again to go ahead 5-3 when Williams's shot was called long on an overrule by the chair umpire.
Helped by four errors from Williams, Mauresmo then served out the match.
"Everything went wrong for me," Williams said afterwards. "I was making too many errors and struggling with my serve. I guess that sums it up. You can't win a match with a second serve.
"There was nothing in particular she did. When I lose a match it's usually because of how I played. In the end it's better to lose in Rome than in Paris."
The American's only other loss this year came against Justine Henin-Hardenne in the final of a tournament in Charleston, South Carolina last month. Her records is now 26 wins and two losses.
Williams had cruised through the first set in just 21 minutes as Mauresmo – the No 4 seed from France – won just four points in the first five games.
"I had to stay in there and wait for a chance to play my game," said Mauresmo, who had never beaten Williams in five previous encounters. "I think I realised I could beat her only in the last two games. That's when I had my chance and I took it."
Mauresmo is attempting to win her second title of the year after defeating Williams's sister Venus in the Warsaw final two weeks ago. She beat Jennifer Capriati in the quarter-finals on Friday.