Shakhtar Donetsk coach Mircea Lucescu has said the UEFA have not yet put in an official request to the club to bar Fred from playing any of their games.
The under-scanner midfielder was fielded against Fenerbahce in their Champions League qualifier game on Tuesday against the wishes of the European football governing body.
The game saw the debut of ex-Manchester United stars Nani and Robin van Persie for the Turkish giants.
Fred, 22, has reportedly tested positive for a banned substance – Hydrochlorothiazide – and the player's career hangs in balance, as reports of the second test can be the be-all-and-end-all for the player.
The midfielder – who participated with the senior national side for Brazil in the Copa America 2015 – may face an indefinite ban from the game after his B samples emerge.
But despite that, Lucescu awarded a starting role to the player in their goalless draw against the Turkish giants on Tuesday in Istanbul, against the wishes of the UEFA.
The manager has reasoned that he took the step since there wasn't any official request from the governing body.
"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," the Shakhtar coach said.
"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," Lucescu added.
According to reports, the youngster was administered with the illegal drug while he was participating in the Copa America this summer in Chile.
The development has made the Shakhtar coach appalled. Lucescu has now asked the Brazilian team doctor to explain everything.
"It is very hard to say what really happened. I guess the Brazil team doctor should be responsible for things like that," the Shakhtar coach said.
"It would be very sad if such a young player is suspended for some time."
Fred was part of Brazil's first two group games against Peru and Colombia respectively at the Copa America in Chile.
An official announcement from the Brazilian Football Federation (CBF) is expected to come at the end of the day, while UEFA is also expected to clarify before Shakhtar and Fenerbahce go head-to-head in the second leg clash on 5 August.