Li Na calls it quits

Li Na, a two-time Grand Slam champion from China who took tennis in Asia to a new level, has retired due to recurring knee injuries.

The 32-year-old Li posted a statement on social media sites on Friday, ending a week of intensifying speculation she would announce her retirement ahead of the new WTA event at Wuhan, her home town.

Li won the 2011 French Open, becoming the first player from China to win a Grand Slam singles title, and clinched the Australian Open title in January in her third trip to the final at Melbourne Park to reach a career-high No 2 ranking.