ISTANBUL, Oct. 25 (Xinhua) -- Li Na swept injured Victoria Azarenka 6-2, 6-1 to become the first Chinese to enter the semi- final of the WTA Championships on Friday.
The Chinese, ranked fifth in the world, wrapped up the group stage 3-0 on the expense of the Belarusian, who beat her twice at the WTA Championships in 2011 and 2012.
Azarenka hurt here back in the sixth game of the first set when she took a medical timeout. She received several treatment during changeovers but had no sign of recovery from the pain. She finished 1-2 in the group.
Azarenka's loss gave way to Jelena Jankovic to advance into the semis before she had to play Sara Errani late Friday.
Jankovic will face world No. 1 Serena Williams, who swept here group with 3-0, in the semi-finals while Li will take on either Petra Kvitova or Angelique Kerber.