Result: Agnieszka Radwanska edges out Vera Zvonareva

Agnieszka Radwanska has progressed through to the semi-finals of the WTA Championships after she defeated Vera Zvonareva in three sets.

Zvonareva got off to the best possible start as she overpowered her opponent to take the first set 6-1.

However, the second was similarly one-sided for Radwanska, who claimed it 6-2.

The third provided the Istanbul crowd with plenty of nail-biting action as Zvonareva blew three match points on the way to her defeat.

At 5-3 she couldn't close out the match and Radwanska came back to take it 7-5 and book her place in the final four.