Rio de Janeiro: The Chinese Swimming Association has confirmed Chinese swimmer Chen Xinyi has failed a doping test at the Rio Olympics.
Chen, who came fourth in the women's 100m butterfly final, tested positive for hydrochlorothiazide (HCTZ) on Sunday, a diuretic banned for its potential to mask the use of other performance-enhancing drugs.
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The association said the 18-year-old had now supplied her "B" sample for further testing and requested an evidentiary hearing, according to the official Xinhua news agency.
The revelation was headline news on China's major internet news sites and was met widely with shock on Chinese social media, with Chen Xinyi the top-searched item on China's Twitter-like Weibo on Friday afternoon. "If this is true, what I want to know is who made you take the drugs?" one comment read.
Some revelled in the schadenfreude given the furious reaction to Mack Horton calling Sun Yang a "drug cheat", though most said Chen's positive test had no connection to the multiple Olympic gold medallist.
"This has nothing to do with Sun Yang, and Horton will still be his bitch in the 1500m," one comment read, referring to the 1500m freestyle final on Sunday which will see the two rivals face off once again. "This is a real slap in the face," another read, "Horton must have passed out with laughter right now."
The swimming association said it was "paying great attention" to the incident and has told Chen to cooperate with the investigation. It said it "resolutely opposed" the use of performance enhancing drugs and that it would cooperate with and respect the final decision of the Court of Arbitration for Sport.
Chen was set to be the subject of a ruling by the Court of Arbitration for Sport on Thursday night, Estadao, a major Brazilian newspaper reported. A FINA spokesperson declined to comment when contacted by Fairfax Media.
The news is expected to further inflame the already volatile mood at the Olympic pool, which has seen unprecedented drama as athletes speak out about doping.
Chen finished fourth in the women's 100m butterfly final and was due to swim in the heats of the 50m freestyle event on Friday morning in Rio.
Reports suggest she was tested prior to arriving in Rio and swam without knowing the result of the alleged positive result. It was further reported that she was told of the positive two days ago and has taken the case to CAS to attempt to avoid a suspension.
Chinese swimmers have already been in the spotlight in Rio since Australia's 400m freestyle champion Mack Horton called rival and silver medallist Sun Yang a "drug cheat" prior to their race.
Sun was suspended for three months in 2014 but said he was taking angina medication that wasn't previously on the WADA list of banned substances.
Chen is the first Chinese athlete to test positive at an Olympics since 1992.