French second seed Marion Bartoli enjoyed two match wins in one day, including a straight-sets defeat of US Open champion Samantha Stosur, to take the Japan Open title on Sunday.
After rain had forced organisers to hold the semi-finals and final on the same day, Bartoli beat German third seed Angelique Kerber 6-1, 7-6 before flattening Australian Stosur 6-3, 6-1 in the final.
Bartoli's seventh career title, and second of the year, kept alive her hopes of taking the last remaining spot in the season-ending WTA Championships in Istanbul.
"I'm very happy with the way I played this week," said Bartoli, who won in Eastbourne in June.
"It has been a good season; I felt my level dropped in August, especially at the US Open, but now I'm back playing well again. Obviously to win a title is great. Now I have two titles this year so I'm really happy."
Stosur, who is already sure of her place in Istanbul, was taken to three sets in her semi-final before beating 28-year-old Zheng Jie of China 7-6, 3-6, 6-3.
The WTA championships will feature the world's top eight players and run from October 25 to 30.
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