Italian veteran Flavia Pennetta on Friday scored a gritty victory over world number one and defending champion Caroline Wozniacki of Denmark to set up a semifinal clash against Agnieszka Radwanska of Poland at the China Open.

Wozniacki took the first set routinely but faded off in the last two sets, slumping at 3-6, 6-0, 7-6 (2) to the 26th ranked Pennetta in two hours and 14 minutes.

Radwanska, seeded 11th in the elite tournament, had a much easier time of it in the quarterfinals when Serb Ana Ivanovic pulled out while trailing 6-3, 3-2, citing a back injury. The former French Open champion also retired from the Beijing Olympics three years ago on the same court. - http://english.cri.cn