Agnieszka Radwanska has secured her place in the WTA Championship final with a victory in three sets over Garbine Muguruza.

Radwanska took the game to the Spaniard in the early stages of the set, securing an early break of serve. However, Muguruza battled back to level the set with a break of her own to take it to a tie-breaker.

The number two seed upped the quality of her game to win the crucial points to clinch the tie-breaker 7-5.

Radwanska responded in the second set by attacking the Spaniard's serve, which yielded three breaks. Muguruza tried to fight back, but the Pole managed to hold out to secure a 6-3 win to set up a decider.

The two players battled out a tight contest in the third as they both took advantage of break points, but the set looked to be heading towards a tie-breaker before Radwanska clinched another break to secure a 7-5 win.

The number five seed will play either Maria Sharapova or Petra Kvitova in the final.