QINGDAO -- Olympic champion Xu Lijia of China has pulled out of ISAF World Cup leg in Qingdao due to injury, organizers said on Wednesday.

Liu Wei, director of the competition organizing committee, said that Xu was injured during the first day's Laser Radial race and she formally withdrew on Wednesday.

"Doctors said her shoulder injury was severe. She will return to Shanghai to receive a treatment tomorrow," said Liu, adding that Xu might have to miss the rest competitions of this year.

Xu, 26, won a bronze medal in women's Laser Radial class at the 2008 Olympics and a gold medal in the same event at the 2012 Games.

The ISAF World Cup Qingdao leg kicked off on Monday.