WTA semis: Williams-Wozniacki, Halep-Radwanska

SINGAPORE (AP) Serena Williams will meet Caroline Wozniacki in the semifinals of the WTA Finals while Simona Halep will take on Agnieszka Radwanska.

On the final day of group games on Friday, Maria Sharapova, Petra Kvitova and Ana Ivanovic all had their destinies in their own hands yet failed to take the opportunities to progress.

Sharapova needed to beat Radwanska in straight sets to progress but collapsed from a set and 5-1 up to lose the second set, spurning three match points.

Sharapova's elimination, despite ultimately winning in three sets, conceded the year-end No. 1 ranking to Williams.

Kvitova needed to beat Wozniacki but lost 6-2, 6-3.

Ivanovic needed to beat Halep in straight sets. She came from two breaks down to win the first set, but lost the second.

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