Barcelona take nine-point lead as Madrid held by Betis
In three days, Barcelona have enjoyed seeing rival Real Madrid take two blows.
After beating Madrid 1-0 in the first leg of the Copa del Rey semi-finals at the Santiago Bernabeu Stadium, Barcelona kept their title-chasing momentum in the Spanish league by defeating Valencia 1-0 on Sunday and increased their lead to nine points.
Second-placed Madrid couldn't keep pace with the Catalan club when held to a 0-0 draw at Real Betis later.
Raphinha scored a first-half winner for Barcelona, who had a penalty miss from Ferran Torres early in the second half and then had defender Ronald Araujo sent off.
Madrid were mostly in control against Betis, but Vinicius Junior, Karim Benzema and Rodrygo failed to capitalise on their scoring chances.
Barcelona and Madrid will play their final league clash on March 19 at the Camp Nou.
"It's not over yet," Madrid's Lucas Vazquez said. "We know it's going to be tough, but we will fight until the end. We really think we can make a run."
Barcelona had lost two in a row - against Manchester United in the Europa League and Almeria in the league - before coming up with the big Copa victory against Madrid at the Bernabeu.
Raphinha scored against Valencia with a header after a well-placed pass by Sergio Busquets in the 15th minute. Torres missed the penalty in the 55th and four minutes later Araujo was sent off for stopping a breakaway.
Barcelona got the win despite still missing some of their top players, including Robert Lewandowski, the league's leading scorer. Ousmane Dembele and Pedri also didn't play because of injuries, while playmaker Gavi was out because of a yellow-card suspension.
"We are not being effective up front and end up suffering to close out matches," said Barcelona coach Xavi, who watched from the stands because of a suspension.
Madrid were without midfielder Luka Modric because of a yellow-card suspension. Carlo Ancelotti's team are winless in three straight matches after defeating Liverpool 5-2 in the first leg of the round of 16 in the Champions League.
Benzema scored from a free kick in the 12th but the goal was called off after video review because the ball deflected slightly off the arm of Madrid defender Antonio Rudiger.
Betis saw their three-game winning streak end but remained in fifth place, three points behind fourth-place Real Sociedad in the final Champions League spot.
Valencia went into the Camp Nou inside the relegation zone and missing several players because of injury, including veteran striker Edinson Cavani. They are 19th place, two points from safety.
Valladolid defeated Espanyol 2-1 in a match between two clubs trying to stay far from the relegation zone.
Ivan Sanchez scored in the 25th and Alvaro Aguado in the 62nd for Valladolid, who moved to 14th place, two points clear from the drop zone.
Martin Braithwaite netted in the 87th for Espanyol.
Seventh-place Rayo Vallecano and eighth-place Athletic Bilbao drew 0-0 in a result that kept the clubs from moving up into the European qualification places.
Athletic nearly came away with the road win when Nico Williams' stoppage-time shot struck the crossbar.