China's greatest athlete Liu Xiang retires

China's greatest track and field athlete, 110m hurdler Liu Xiang, has announced his retirement at the age of 31.

Xiang, the gold medal winner at the 2004 Olympics in Athens, said he had “no choice” but to end his career which has been ravaged by injuries.

"From today, I will end my life as a professional athlete and retire formally," he wrote on social media.

 "This is a decision made after long deliberation. I am deeply reluctant and feel pained, but I have no choice.”

The Shanghai-born athlete became a huge hero in China where he is loved as much for his heart-breaking setbacks as well as his achievements.

His Athens victory was China’s first Olympic gold in track and field.

He was hotly tipped for gold at the 2008 Olympic Games in Beijing, but limped out of the first heat, shocking tearful home fans at the Birds Nest Stadium.

Liu suffered another agonising exit at London 2012, clattering into the first hurdle in his opening heat.

After being helped up, he hopped the length of the track before symbolically kissing the last barrier and exiting the Olympic arena – as it turns out, for the last time.

Liu will be remembered in China as the man who proved that Asian athletes can compete with the world's best in sprint sports, particularly when he was on world-beating form ahead of Beijing 2008.

He arrived at the Games after breaking the world record with a time of 12.88 seconds in 2006, and winning the world title in 2007.

His coach Sun Haiping was quoted in Chinese media last week that he was "preparing" to retire, fuelling speculation he would finally draw the curtain on a remarkable career.

In his retirement statement, Liu looked back with "reluctance" to the pivotal Beijing Olympics, when his career began to be severely affected by a right Achilles tendon injury.

"I dreamt about raising the (Chinese) flag," he said, "But the injuries started to torture me just before the race."