The World Anti-Doping Agency has appealed against a decision by swimming's governing body to only give the three-time Olympic champion a warning in a case involving the destruction of a doping control sample, the court said Wednesday.
British newspaper the Sunday Times reported incidents involving Sun when a doping control official visited his home in China last September. A vial of Sun's blood was reportedly smashed with a hammer, and his entourage disputed the official's credentials.
CAS said it has not set a date for the hearing. It is unclear if the appeal case can be resolved before the swimming world championships in July in Gwangju, South Korea. Citing the confidential legal process, WADA declined to say if it will seek a fast-track hearing. Sun's legal team would also have to agree to speed up the process at CAS, which typically takes months to prepare cases.
The 27-year-old Sun served a three-month ban in 2014 for testing positive for a substance then classed as a stimulant. That case was conducted in relative secrecy in China. Sun would face a more severe sanction for a second violation of doping rules.
The freestyle swimmer won gold at each of the past two Olympics, in the 400 and 1,500 meters at the 2012 London Games and in the 200 at the 2016 Rio de Janeiro Games. In Rio, Australia's Mack Horton called Sun a "drug cheat" before taking his rival's 400 title, leaving the defending champion with silver. Horton ignored Sun's attempt to congratulate him in the pool.
Sun also won multiple individual gold medals at each of the past four world championships, which were unaffected by his previous ban. FINA, the governing body of swimming, said Wednesday it "welcomes CAS's scrutiny."
"All of FINA's disciplinary decisions, however, form part of a very robust anti-doping program that has proven highly effective in ensuring clean competition at the World Championships and Olympic Games," the Lausanne-based organization said.
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