China's Tennis Star Li Na Set to Announce Retirement

China's two-time Grand Slam-winner Li Na is poised to retire, state media reported Thursday, in a move which would bring down the curtains on Asia's most successful tennis career.

The sports channel of state-owned CNTV cited Li's agency, IMG, as saying the tennis star would hold a briefing on Sunday to announce the news but also said she might make an official announcement on Friday via social media.

A separate report by CCTV-5, the sports channel of state broadcaster China Central Television, quoted unnamed insiders as saying Li, 32, will announce her retirement because of injuries on Friday.

"According to insiders, Li Na will officially announce her retirement on September 19," CCTV-5 said on its verified microblog.

"She is reportedly retiring because she is unable to continue competing due to her physical condition," it said.

The broadcaster did not give any details about its sources. An employee at the Beijing office of Li's agency, IMG, told AFP that Li's manager was in a meeting and unable to confirm.

CCTV-5's report comes after web portal SINA Sports, also quoting unnamed sources, said IMG would hold a briefing on Friday to announce Li's retirement.

The world number six won the Australian Open in January but her season has been troubled by injury and she has been sidelined since late July with a knee problem.

She was ranked a career-high second in the world after January's Grand Slam win, but has slid down to sixth after missing a string of tournaments including the US Open. In July, Li also split with her influential coach Carlos Rodriguez.

She initially planned to return at the inaugural WTA Wuhan Open, in her home city, which begins Sunday.

Officials at the tournament remained tight-lipped on whether she would be playing, with one telling AFP there had been no official confirmation that she had pulled out.

- Grand Slam champion -

Li originally played badminton after being encouraged in the sport by her father who played professionally. However, she switched to tennis after being convinced by her childhood coach.

She took a break in her career early on to study journalism at university only to return to tennis.

Li became a sporting pioneer in China when she decided to break from the state sports system in 2008 with a group of upcoming players, in a move dubbed by local media "fly alone".