A senior figure in the London 2012 Games has warned against "irresponsible" and "destructive" judgment of the Chinese swimmer Ye Shiwen after a leading coach described her world-record breaking race as "disturbing".
Duncan Goodhew, Olympic Village Deputy Mayor, and a gold medallist in the men's 100 metres breaststroke in the 1980 Moscow Olympics, said competitors were innocent until proven guilty - and that there were always "incredible improvements" in performance at large sporting events such as the Olympic Games.
"There are always incredible improvements in any large sporting event such as the Olympic Games, and of course, in terms of that, innocent until proven guilty," he told ITV Daybreak. "I think it is very destructive and very irresponsible of anybody to accuse people until they are proven guilty."
His remarks were made following rumblings over the remarkable performance of 16-year-old Ye changed to overt suspicion when American coach John Leonard described her world-record breaking race as "disturbing".
China's appalling past record for their swimmers failing doping tests has led to the inevitable suspicions over the teenager, who took five seconds off her personal best and more than a second off the world record in the 400m individual medley.
Ye Shiwen's swim was described as "insanely fast" by previous world record holder Steph Rice - indeed, in the final 50m, Ye swam faster than the men's champion Ryan Lochte.
Leonard, the executive director of the World Swimming Coaches Association, told the Guardian the performance was "disturbing" and "unbelievable".
He added: "We want to be very careful about calling it doping.
"The one thing I will say is that history in our sport will tell you that every time we see something, and I will put quotation marks around this, 'unbelievable', history shows us that it turns out later on there was doping involved.
"That last 100m was reminiscent of some old East German swimmers, for people who have been around a while. It was reminiscent of 400m individual medley by a young Irish woman in Atlanta."