Turkish outfit Fenerbahce have complained to UEFA after Shakhtar Donetsk played Fred against them in their Champions League qualifier, despite the Brazilian facing doping accusations.
The two teams played out a goalless draw in the first leg of their third qualifying round match on Tuesday evening, with Fred starting the clash and being substituted late on.
The 22-year-old reportedly tested positive for using the banned diuretic hydrochlorothiazide at the Copa America, but Shakhtar manager Mircea Lucescu has insisted that he was cleared to play the midfielder.
"Before the game, UEFA advised us not to include him but we had not received any official documents and this was just a verbal recommendation," Lucescu is quoted as saying by BBC Sport.
"There is no specific statement on this matter for now and we are still waiting for the results of the B sample.
"I have talked to the team and the player personally. When the official decision arrives, of course, we will stick to it."
Fred has spent the past two seasons at Shakhtar.
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