Martin Rogers

USA TODAY Sports

RIO DE JANEIRO — The Court of Arbitration for Sport (CAS) confirmed Friday that Chinese swimmer Chen Xinyi would be suspended from competition at the Rio Olympics after failing a doping test.

The 18-year-old, seen as one of the rising stars of the sport, tested positive for hydrochlorothiazide, a masking agent, in a blood test administered before the Games. She is the first swimmer to be banned during an Olympics since 1992.

Chen’s case was heard by CAS on Thursday night, with the swimmer accepting a “provisional suspension on a voluntary basis,” meaning she would be prohibited from taking any further part at Rio.

Rio 2016 Olympics Medal Count

She had finished fourth in the 100-meter women’s butterfly earlier in the meet and was due to compete in the 50-meter freestyle on Friday morning, but she did not show up and was listed as a DNS (did not start) on the official records.

Chen was also considered likely to swim for China in the butterfly leg of the 4x100 medley relay.

CAS said it would continue to consider the case and would issue a final ruling “before the end of the Games.”

In other CAS decisions on Friday, the Anti-Doping Division declared Polish weightlifter Tomasz Zielinski ineligible to compete and excluded from the Games for a positive test for an anabolic steroid.

It also declared Bulgarian 3,000-meter steeplechaser Silvia Danekova ineligible and excluded from the Games for testing positive for EPO.

Both athletes previously competed in the London Olympics.