The Chinese swimmer Sun Yang has had his eight-year ban for doping violations referred back to the Court of Arbitration for Sport after an appeal to a Swiss court.
Sun was banned for eight years by CAS in February after it accepted an appeal from WADA against a decision by swimming body FINA to clear Sun of wrongdoing for his conduct during a 2018 test.
Sun appealed against that decision and WADA has issued a statement sayng they have been informed the Swiss Federal Tribunal had upheld a challenge but not made any comment on the substance of the case.
"WADA will take steps to present its case robustly again when the matter returns to the CAS Panel, which will be chaired by a different president," the statement said.
Sun, the reigning world and Olympic champion in 200m freestyle, was banned after he and members of his entourage were found to have smashed vials containing blood samples taken at an out-of-competition test in September 2018.
The 29-year-old, who won two gold medals at the 2012 London Games and another at Rio de Janeiro in 2016, is a controversial figure in the sport.
He served a three-month doping suspension in 2014 for taking the stimulant trimetazidine, which he said he took to treat a heart condition, while Australian swimmer Mack Horton openly called him a drug cheat at the 2016 Rio Olympics.
Horton refused to share the podium with Sun at the 2019 world championships in South Korea, a move that was applauded by other swimmers but condemned by FINA.
The New York Times reported Sun's lawyers had successfully argued to the Tribunal the head of the CAS Panel had made public comments that expressed anti- Chinese sentiments.
Sun has questioned the credentials and identity of the testers and has constantly proclaimed his innocence.
-Reuters