Zinedine Zidane says Marcelo will only make his Real Madrid return against Roma on Wednesday if he is 100 per cent fit.
Marcelo sustained a shoulder injury against Granada on February 7 and subsequently sat out the 4-2 victory over Athletic Bilbao, with Dani Carvajal filling in at left-back.
The Brazilian has been included in the match squad for the Champions League last-16 first-leg against Roma at the Stadio Olimpico this week.
However, coach Zidane insists the left-back will only play if he is ready.
"Marcelo will only play if he is 100 per cent," said the Frenchman. "I think he is, but we will see what happens.
"He should sleep well and tomorrow we will see, but for a competition and a game like this you have to be at 100 per cent."
Zidane has been impressed with his side's preparation and believes they can pick up a positive result in Rome.
"You have to do the same as we do in La Liga. Roma are a difficult team, and we are away from home, but we had a good week and I am confident to do well tomorrow," he added.
"We want to progress. We will try to give our best and we shall see. We have to be concentrated, the players are, and it is important to me. When I see that, I'm more relaxed."
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