Olympic swimming champion Sun Yang's anti-doping case - the Chinese star faces an eight-year ban over a missed drug test - will not be settled before mid-January.
The Court of Arbitration for Sport said "concerns were raised" about the translation of Sun's testimony from Chinese into English at a hearing on November 15. The triple Olympic gold medal winner, who served a doping ban in 2014, is accused of smashing a blood vial with a hammer after a visit by testers last year.
Concerns were raised over the quality of the interpretation of Yang's testimony, the court said.
Sun's hearing, the first in public in 20 years, was beset by interpreting errors between Chinese and English. The CAS noted that the translation service was provided by Sun's camp.
World swimming body Fina said in January that Sun had used a hammer to smash a vial of his own blood during a testing session, but it cleared him of violations as testers failed to produce adequate identification. That decision outraged the World Anti-Doping Agency, which went to the CAS.