Sloane Stephens beat Kiki Bertens at the WTA Finals, in a result that spared US Open champion Naomi Osaka early elimination.

The American, 25, won six of the last seven games to claim the match 7-6 (7-4) 2-6 6-3.

The victory means all four players in the Red Group can still qualify or be eliminated going into the final games.

Osaka has lost both her round-robin matches, but can progress if she wins and the other result goes her way.

In Friday’s final round of fixtures, Osaka plays Bertens while Stephens faces Angelique Kerber, who beat Osaka earlier on Wednesday and has one win from two.

Stephens and Bertens, 26, traded breaks throughout in a match which saw momentum change regularly.

Fifth seed Stephens won the first-set tie-break, before Bertens broke three times in the second set to win it in 36 minutes.

The third set continued the trend as the Dutchwoman won the first two games before Stephens took the match away from her. The 25-year-old now has two wins from two in the group stage, while Bertens has one.