In-form Real Madrid striker Karim Benzema is recovering from a muscle strain but was left out of Jose Mourinho's squad for Saturday's trip to Athletic Bilbao as a precaution, the club said on Friday.
Benzema injured himself on duty with France last month and missed last weekend's 1-0 defeat at Sporting Gijon and Tuesday's 4-0 Champions League victory over Tottenham Hotspur. Germany midfielder Sami Khedira is suffering from flu and will also miss the game at the San Mames, Real said on their website.
Second-placed Real are eight points behind champions Barca, who host bottom club Almeria on Saturday, with eight games left.
They meet their great rivals in La Liga on April 16, play in the final of the King's Cup on April 20 and are almost certain to clash in the Champions League semi-finals after both recorded comfortable quarter-final first leg wins this week.
The inclusion of Cristiano Ronaldo and Marcelo, who have just returned from injury, in the squad for the Bilbao game shows Real have not given up on catching Barca, according to assistant coach Aitor Karanka.
"The squad proves that our only intention is to win. We are taking all the players we have available," Karanka, standing in for Mourinho, said at a news conference.
"I played at this club for five years and if one thing is certain no player or coach who has passed through has thrown in the towel while there is still a chance."
Barca goalkeeper Victor Valdes said it was positive for the sport that there would likely be four "clasicos" between Real and Barca in coming weeks.
"The more Madrid-Barca games the better," the Spain international, who along with midfielder Sergio Busquets is suspended for the Almeria game because of accumulation of bookings, said in a TV interview late on Thursday. "It's more intense and better for football."
Bilbao coach Joaquin Caparros, who played in Real's youth ranks, is sure they will fight for the title until the end and does not expect an easy ride for his team on Saturday.
"Madrid will come here to pressure us and will be the unit they have shown themselves to be up to now: a very good team, with very direct players, with a lot of shooting ability, very physical," he said at a news conference on Friday. "We have to be at the level of the best Athletic."
New Almeria coach Roberto Olabe, appointed last week to replace the sacked Jose Luis Oltra, said he would not have signed a contract until the end of the season if he did not believe the club were capable of avoiding the drop.
"I have found a group of players who are down because they are the first ones to feel concern about the situation we are in," Olabe told a news conference on Friday. "We have to change this dynamic of worrying because it won't get us anywhere."
Valencia host local rivals Villarreal on Sunday in a clash between third and fourth that could be decisive in their battle for the automatic berth in next season's Champions League.
