WTA Tour

Sam Stosur handed Li Na her worst loss in almost five and a half years to make the semifinals.

The semifinals were already set, but first alternate Marion Bartoli had a point to prove Friday.

Petra Kvitova beat Agnieszka Radwanska in straight sets to keep her out of the semifinals.

Victoria Azarenka is the first player into the semifinals of the TEB BNP Paribas WTA Championships.

Kveta Peschke and Katarina Srebotnik are the top seeds and will square off with Vania King and Yaroslava Shvedova in Saturday's semifinals.

Aga Radwanska's nail-biter over Vera Zvonareva means the battle for the semifinals goes to Friday.

Petra Kvitova beat Caroline Wozniacki in straight sets to become the second player into the semis.

Li Na continued her mastery over Maria Sharapova in her first ever match at the year-end finale.

Vera Zvonareva fired 49 winners to upset the world's No.1. Victoria Azarenka and Li Na also won.

Victoria Azarenka lost just five points in her first seven service games to beat Sam Stosur.