The Catalans can go back top before Madrid visit Betis on Sunday
Barcelona must pick themselves up after Clasico disappointment. They host Real Sociedad on Saturday at Camp Nou, with Madrid not playing until Sunday night, at Real Betis.
Real Sociedad and Barca are two sides that play attractive football - and Messi has not been able to score against an Imanol Alguacil side.
Martin Braithwaite may get his first chance to start after two bright cameos. That could mean a classic 4-3-3. The former Leganes striker doesn't lack confidence.
Arthur will not be playing after picking up an ankle problem and Barca could opt for Ivan Rakitic in his place.
If Barca win they will go back top of the league before Madrid play at the Benito Villamarin. That would put pressure on Zinedine Zidane's side as the run-in starts, with 12 games to go and no clear favourite.