
Petra Kvitova of Czech Republic competes during the WTA Finals round robin match against Angelique Kerber of Germany held at Singapore Indoor Stadium in Singapore, Oct. 26, 2015. Angelique Kerber won 2-0. (Xinhua/Then Chih Wey)

Petra Kvitova of Czech Republic competes during the WTA Finals round robin match against Angelique Kerber of Germany held at Singapore Indoor Stadium in Singapore, Oct. 26, 2015. Angelique Kerber won 2-0. (Xinhua/Then Chih Wey)