A persistent ankle injury threatens to jeopardise Ye Shiwen's world championships campaign as China's double Olympic champion prepares to race in Sunday's 200m individual medley heats and final, reports Xinhua.

"I twisted my right foot ankle a year ago, and I did not know there is a broken bone inside until recently," Ye told the Chinese news agency.

"It has been affecting my training, so I was planning to pull out of the competition in Kazan, but I still decided to come. I will try my best."

The 19-year-old sent shock waves through women's swimming at the London Olympics when she won the 200 and 400m IM titles.

She courted controversy in London by storming through her last lap in the 400m IM final quicker than men's champion Ryan Lochte, triggering accusations of doping, before the then 16-year-old added the 200m title.

She bombed at the Barcelona world championships in 2013 when she failed to medal, but bounced back from a spell in the doldrums by completing the 200 and 400m individual medley double at last year's Asian Games.

She won the Chinese nationals earlier this year, but Hungary's double world champion Katinka Hosszu is the favourite in Kazan to defend both the 200m and 400m IM golds she won in Barcelona.
Source: AFP