Beijing: Defending champion Caroline Wozniacki suffered a humiliating 3-6, 6-0, 7-6 defeat in the China Open quarter-finals as Italian Flavia Pennetta ran rampant on Friday.

The world No. 1’s game collapsed in the second set and she was repeatedly left stranded by Pennetta’s repertoire of lobs, volleys and powerful baseline returns. Facing match point, Wozniacki staged a dramatic comeback to force a tie-break in the third set but Pennetta superbly lobbed the flat-footed Dane to seal the match.

Former world No. 1 Ana Ivanovic became the latest high-profile player to exit the tournament when the Serb retired from her quarter-final against Agnieszka Radwanska with back problems.

Meanwhile, Leander Paes and Mahesh Bhupathi crashed out of the men’s doubles, losing to Croats Marin Cilic and Ivan Ljubicic in straight sets in the quarter finals. The fourth seeds, who had won the Beijing title in 1997, went down 2-6, 3-6.

Cilic and Ljubicic will next take on Robert Lindstedt of Sweden and Horia Tecau of Romania.