Serena Williams and Li Na have advanced to the final of the WTA Championship in Istanbul, Turkey.
Li Na beat Petra Kvitova 6-4, 6-2 in just over an hour and a half.
Serena Williams won the first set against Jelena Jankovic 6-4, then played a distracted second set, getting broken twice, to lose it 2-6. In the third set, Williams was up a double break, and served for the match at 5-2, when Jankovic broke back, saving a match point, then proceeded to win the next two games. Williams finally closed out the match after serving for it a second time, closing it out 6-4, 2-6, 6-4.
Williams and Li Na will play the WTA Championship final on Sunday. It will begin not before 10 P.M. EDT.