The International Olympic Committee's chief doping expert says he has no reason not to "applaud" the achievements of Chinese swimmer Ye Shiwen in the 400m individual medley on Saturday night.
Ye, 16, smashed her personal best for the event by five seconds, set a new world record and swam a faster 50m final leg than US superstar Ryan Lochte in the men's event earlier in the session.
The next day she made clear her intention to dominate the 200m IM as well and inadvertently sparked a storm of speculation about whether she is clean.
Critics are pointing to Ye's former teammate and fellow teenager, Li Zhesi, who tested positve for blood-boosting drug EPO six weeks ago, and asking if China's bad old habits of the 1980s and early 90s are back.
Professor Arne Ljungqvist, chief medico at the IOC, was peppered with questions about the Chinese team and drugs testing at a media briefing on Monday.
Ljungqvist said if he did have doubts he would keep them to himself and have the matter looked into, but that he had no doubts about the swimmers so far.
"I say no, I have not personally any reason other than to applaud what has happened until I have further facts," he said.
As a medal winner, Ye was automatically tested after the 400IM final.
Ljungqvist was also asked if the IOC would consider targeting the Chinese team for testing. He said: "There are different reasons as to why we target certain athletes or a certain group of athletes.
"On the other hand, should a sudden rise in performance or a surprise win be primarily suspected for being a cheat, sport is in danger for sure, because it partially ruins the charm of competitive sport if a surprise win is surrounded by suspicion and question marks.
"Of course should a sudden raise in performance occur in a particular person, we could regard that as possibly a reson to do it, but I would rather say that it's tragic if that should be the primary reason for doing a test."
Beijing triple Olympic gold medallist and former 400m IM world record holder Stephanie Rice said Ye's time in the final 100m freestyle leg on Saturday was "insane". But Rice stayed well away from doping speculation.
"Oh I have no idea, I wouldn't want to get into that at all," Rice said. "Fifty-eight [seconds] is an insanely fast swim but I know she's a good freestyler. I was next to her at worlds in the 200m IM last year and she came home over the top of me in that freestyle leg and I'm not exactly a bad freestyler. She's a gun."
Two former Chinese officials recently made allegations of state-sponsored doping programs in the 1980s and 90s, in which athletes often did not know what they were being injected with.
''It was rampant in the 1980s,'' former chief medical supervisor to the Chinese Olympic team, Xue Yinxian told Fairfax last week. ''One had to accept it.''
- FFX Aus