The club stated this morning: "Chelsea Football Club can confirm the Football Association recently contacted our player Mykhailo Mudryk concerning an adverse finding in a routine urine test.
"Both the Club and Mykhailo fully support The FA’s testing programme and all our players, including Mykhailo, are regularly tested.
"Mykhailo has confirmed categorically that he has never knowingly used any banned substances. Both Mykhailo and the Club will now work with the relevant authorities to establish what has caused the adverse finding.
"The Club will not be commenting any further."
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