The world's two richest clubs are scrapping it out in glorious isolation at the top of the table, Barca eight points clear of second-placed Real with five matches left. Valencia are a distant 25 points off the pace in third.
Barca can take a step closer to their third consecutive league crown with a win at free-falling Real Sociedad on Saturday, the visitors boosted by Wednesday's 2-0 first leg victory over Real at the Bernabeu.
Real test their powers of recovery on Saturday at home to 17th-placed Real Zaragoza, a side they crushed 6-0 in the corresponding fixture last season.
"Maybe Barca won't come with the whole team as they have a very important knockout match to play and a comfortable advantage in the league," Sociedad defender Jon Ansotegi told reporters.
"(Barca's reserves) are at the club for a reason and those that come here will be among the best players in the world."
Bench-warmers Gonzalo Higuain, Karim Benzema and Kaka, who cost more than 100 million euros in total, helped Real win 6-3 at Valencia last weekend and will again be unleashed on cash-strapped Zaragoza who have just one away victory this season.
RELEGATION MIRE
Valencia and Europa League semi-finalists Villarreal, in fourth, hold respective six-point leads in the fight for the Champions League qualification places, and all the top four play teams deep in the relegation mire.
Unai Emery's Valencia visit 18th-placed Osasuna on Sunday after Villarreal host 14th-placed Getafe, who have just been taken over by the Dubai-based Royal Emirates Group.
Bottom club Almeria (26 points) are 10 points from safety and have little chance of survival but there are only five points separating eight sides between Hercules (33), in 19th, and 12th-placed Sociedad (38).
One of the most significant clashes on Sunday is between 16th-placed Malaga, one point above the bottom three with 36 points, and visiting Hercules.
"Against a direct rival like Hercules it's almost more than three points at stake," Malaga midfielder Recio told reporters.
"There are some very important games this weekend when rivals to avoid the drop could slip up. From my point of view this is the real final of the five games we have left."
Malaga, who were bought by a member of the Qatari royal family last year and are coached by former Real Madrid boss Manuel Pellegrini, have won four and drawn one of their last six matches.
They have been boosted recently by the return from long-term injury of Brazilian forward Julio Baptista, who has scored three goals in two games.
