Third-seeded Alize Cornet of France edged Eugenie Bouchard of Canada 7-5, 6-7 (5), 6-3 on Friday to reach the final of the Strasbourg International.
Cornet broke the Canadian teenager twice in the last set of the French Open clay-court tuneup and saved six break points.
Bouchard, 19, had reached the semifinals of a WTA event for the first time in her career. She was looking to become the first Canadian to win a tour event since Rebecca Marino in 2011, and the second to win the Strasbourg title, which Carling Bassett captured in the 1980s.
The Westmount, Que., native was ranked 93rd in the world on the most recent list, and should jump several spots in next week's rankings.
Bouchard will have a tough challenge right away at the French Open, as she was drawn against Bulgaria's Tsvetana Pironkova, a one-time Wimbledon semifinalist.
The winner of that match would likely face defending champion Maria Sharapova, who Bouchard has described as her idol.
Cornet will face Lucie Hradecka of Czech Republic for the Strasbourg final. Hradecka defeated Italy's Flavia Pennetta, 1-6, 6-3, 6-1.
Both Hradecka and Pennetta were playing for the second time Friday due to rain delays earlier in the week.
Pennetta had dismissed Misaki Doi of Japan 7-5, 6-3 while Hradecka downed Johanna Larsson of Sweden 7-5, 6-3.