Enzo Maresca has thrown his support behind Mykhailo Mudryk, saying he believes the Chelsea winger’s insistence that he is innocent of taking a banned substance.

Although Maresca admitted Chelsea could be forced into the January transfer market if their £89m attacker is hit with a long ban for a positive drug test, the head coach said all is not lost for the 23-year-old. Mudryk, who has been provisionally suspended by the Football Association, is fighting to clear his name after meldonium was detected in a positive A sample.

The Ukraine international is waiting to find out if a B sample backs up the initial result, but he issued a statement on Tuesday denying any wrongdoing and he still enjoys the backing of his club. “We trust Misha and we support Misha,” Maresca said. “Trust means that we believe Misha.”

The FA could ban Mudryk for four years if his guilt is proven. The former Shakhtar Donetsk attacker, who has struggled since joining Chelsea in January 2023, is being assisted by the law firm that helped Juventus’s Paul Pogba in his doping case. Pogba’s four-year ban was cut to 18 months after an appeal to the court of arbitration for sport.

Mudryk, who has not featured in Chelsea’s past five games, has said the positive test came as a shock. Maresca has spoken to the player and is confident he can mount a comeback, no matter how his case plays out. “I think he is going to come back,” the Italian said. “The only thing is we don’t know when.”

Chelsea, who host Shamrock Rovers in the Conference League on Thursday, have plenty of options in attack and Mudryk’s absence could lead to opportunities for the 18-year-old winger Tyrique George.

However, Maresca, who believes football does not have a wider doping problem, has not ruled out signing someone next month. “We have now games before January,” he said. “We have Everton, Fulham and Ipswich.

“After these three games we are going to sit and we are going to decide if we need to do something. Tyrique is going to get minutes and we are going to try to help him to improve day by day.”

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Chelsea have been boosted by the 18-year-old right-back Josh Acheampong extending his deal until 2029. Acheampong, who has been linked with Real Madrid and Liverpool, had less than two years left on his contract and there were doubts over his future.

“Josh has been quite clear,” Maresca said. “In pre-season, after two or three days he really impressed me. Since pre-season I was trying to understand the situation with him in terms of contract. Now we are all happy because we are all convinced that Josh can be a great player for this club.”