MADRID May 9 (Reuters) - Maria Sharapova fought back from a set down to oust China's Li Na 2-6 7-6(5) 6-3 on Friday and claim a place in the last four of the Madrid Open.
Russian Sharapova, the eighth seed, showed all her battling qualities on the clay at the futuristic Magic Box arena to dispatch the world number two and set up a semi-final clash with third-seeded Pole Agnieszka Radwanska or French qualifier Caroline Garcia.
Sharapova lost to top-ranked American Serena Williams in the 2013 Madrid final and her chances of going one better this year were boosted when Williams withdrew with a thigh injury before her quarter-final against Czech fifth seed Petra Kvitova.
Williams, winner of the last two editions of the tournament and seeking her 60th career singles title, suffered the injury in her first-round match against Belinda Bencic.
With the French Open just two weeks away she decided to pull out to give herself time to recover.
"It's beyond words. It's so frustrating," Williams said in comments released by the WTA. "This is not the way I wanted this week to end."
The 17-times grand slam singles champion had been on a run of 15 consecutive victories in the Spanish capital and her victory over Carla Suarez Navarro in the last round brought up her 650th win on the women's tour.
In Friday's other quarter-final, fourth seed Simona Halep of Romania plays 11th-seeded Serb Ana Ivanovic, with the winner to play Kvitova for a place in Sunday's final. (Reporting by Iain Rogers, editing by Ed Osmond)