Caroline Wozniacki lost her quarterfinal at the Sydney International on Wednesday, opening the way for Petra Kvitova to take over the No. 1 ranking before next week's Australian Open.
Wozniacki, who needed a medical timeout in the final set to have her left wrist taped, lost 3-6, 7-5, 6-2 to seventh-seeded Agnieszka Radwanska of Poland.
Wozniacki's win in the opening set came among five service breaks between the players, and she served for the match at 5-4 in the second before Radwanska began her comeback.
The Danish player seemed to be increasingly bothered by what television commentators said was a sore tendon in her left wrist, and she had it heavily taped after the third game of the final set.