Barcelona boss Luis Enrique will decide an hour before the game if Lionel Messi will start against Real Madrid on Saturday after his return from injury.
The Argentine forward, 28, has been out with a knee injury since 26 September but returned to training this week.
Real, who will overtake Barca at the top of La Liga if they win, have a fully-fit squad.
"We know he won't be 100%. Whether he plays or not, the great news is that he is fit again," Enrique said.
"I don't have things planned yet. I will speak with Leo today and again tomorrow. An hour before the game, things will be decided."
Real striker Karim Benzema, who is under formal investigation in connection with a sex tape blackmail plot but maintains his innocence, has missed the last six games through injury.
"Benzema is in the squad, he trained well and is part of the group," Real manager Rafael Benitez said. "We still have to decide whether he starts or not."