Petra Kvitova has progressed to the semi-finals of the WTA Championships after Lucie Safarova recorded a straight-sets win against Angelique Kerber.
Earlier on Friday, Garbine Muguruza beat Kvitova in three sets, leaving Kerber requiring just a set against Safarova to make it through to the last four in Singapore.
However, it was Safarova who emerged victorious, winning by a 6-4 6-3 scoreline to allow Kvitova to remain in the tournament.
Saturday's semi-finals will see Muguruza take on Agnieszka Radwanska, before Maria Sharapova faces Kvitova.
