Aravane Rezai won the Tournament of Champions in Bali on Sunday when top seed Marion Bartoli retired with a quad injury after losing the first set 7-5.
The win gave Rezai the second title of her career following success at Strasbourg in May and lifted her into the world's top 30 for the first time.
"It's a big surprise to finish like that I'm very sorry for her," said Rezai, who earned $200,000 and broke the million-dollar barrier in career earnings over the week.
"She looks like she hurt a lot and I hope it is not a big injury," she added.
Bartoli had broken her fellow Frenchwoman to lead 3-2 but failed to serve out the set at 5-4 and was unable to convert a break point on Rezai's serve at 5-5.
Tenth seed Rezai held for 6-5 and then struck a backhand winner to end a long rally to earn two set points.
Bartoli then walked to the chair wincing in pain and after having her left thigh taped up she immediately double-faulted to lose the set before throwing in the towel.
"I proved to myself I can be at a much better ranking and much better player on the tour," said Rezai after her first win in three meetings with Bartoli.
"I also proved to so many people my family, my parents, my coach, that I can do better and better," she added.
Bartoli was bidding for her third title of the year after winning at Monterrey and Stanford.
