Agnieszka Radwanska outlasted Garbine Muguruza 6-7 (5-7), 6-3, 7-5 to reach her first-ever final at the WTA Finals in Singapore on Saturday (31 October), where she'll meet Petra Kvitovaafter she after outplayed Maria Sharapova 6-3, 7-6 (7-3)

Script:

RADWANSKA bt MUGURUZA

After losing to Garbine Muguruza on four previous occasions this year, fifth seed Agnieszka Radwanska had a point to prove in their semi-final clash at the WTA Finals on Saturday.

At first, it looked as if Radwanska's losing streak against the second seed was set to continue as she squandered a 4-1 lead in the opening set - Muguruza claiming the set by seven points to five in the tiebreak.

But as unforced errors started to creep into the Spaniard's game in the second, Radwanska taking advantage holding her lead to take the set 6-3.

A tense decider saw Radwanska under pressure once more as she was pegged back to 4-all after leading 4-1.

But the Pole held her nerve to edge the victory, winning the third set by seven games to five to earn a place in the final.

It will be Radwanska's first appearance in the championship clash at the WTA Tour Finals - and victory would secure her the biggest title of her career.

KVITOVA bt SHARAPOVA

Petra Kvitova and Maria Sharapova went head-to-head in the other semi-final

After a tightly-contested first few games, a break for Kvitova in the seventh proved decisive - the fourth seed reeling off three consecutive games to claim the opening set 6-3.

But Sharapova retaliated in the second as she stormed to a 5-1 lead.

Kvitova proved more than equal to the Russian's onslaught, though - pushing the set to a tie-break, and taking seven of eight points from 0-2 down.

She closed out the match 6-3, 7-6 (7-3).

She is now just one match away from her second WTA Finals title, after her victory in 2011.

Only Agnieszka Radwanska stands in her way, but she trails their head-to-head series 6-2.