Chelsea manager Enzo Maresca says the club "trust" Mykhailo Mudryk did not knowingly take a banned substance that led to him failing a drugs test.
The Ukraine international has been provisionally suspended by the Football Association (FA) after a routine urine test provided by Mudryk returned an "adverse finding".
The 23-year-old, who is unable to play for or train with the club during his suspension, denies knowingly using a banned substance.
Maresca hopes the winger will quickly be absolved of blame.
"We support Mykhailo and trust means that we believe Mykhailo," said Maresca.