During the US Open Series, Clijsters won her fourth Stanford Classic and finished runner-up to Maria Sharapova at the Tier I San Diego Classic. However, her summer season came to an end when she fell on her left wrist in her opening round match at the Canadian Open. This injury kept her out until late October. She made her return at the Hasselt Cup and won her second consecutive title at the event. Clijsters entered the WTA Tour Championships ranked No. 5 in the world, where all three other players she was grouped with were Russian. Although she lost to her group's top seed, Sharapova, she defeated Svetlana Kuznetsova and Elena Dementieva to advance. Her season ended in the semifinals, where she lost to world No. 1 Mauresmo.