After two straight losses in two different competitions, Real Madrid will be looking to keep its Spanish league lead in tact with a win over Espanyol on Saturday.
Madrid have a game in hand, but a third straight slipup could give the lead to either Barcelona or Atletico Madrid, who play Sunday.
Real Madrid lost to Valencia last week, ending its 22-match winning streak. Atletico, the defending league champion, then beat Real Madrid in the Copa del Rey on Wednesday.
"To speak of a crisis is exaggerated," Madrid coach Carlo Ancelotti said.
Here are some things to know about this weekend's Spanish league matches:
Defending champion Atletico, with striker Fernando Torres back in the team, is building momentum after two league wins and the victory over Madrid in the Copa del Rey.
The addition of Torres gives Atletico coach Diego Simeone the choice of a third striker, adding to the effectiveness of Mario Mandzukic and Antoine Griezmann. Mandzukic has scored six goals in 13 appearances, while Griezmann has eight goals in 17 games.
"Torres' presence transmitted hope and energy," Simeone said of the forward's debut against Real Madrid. "He's strong, powerful, fast and needs a logical amount of time to coordinate better."
With all problems in Barcelona on and off the field, they still have Lionel Messi.
Facing Atletico, the team will be buoyed by Messi's return to fitness after a suspected stomach bug. However, the club said midfielder Xavi Hernandez will be sidelined with a torn calf muscle in his left leg and France defender Jeremy Mathieu is out with an Achilles tendon injury in his left leg.
Carlo Ancelotti, who became the first Madrid coach to lose three consecutive derby matches to Atletico, said he didn't play Cristiano Ronaldo until late in the second half of the cup match because the Portugal forward "was tired."
The Italian coach said both Karim Benzema and Gareth Bale were in good form, but the team lacked depth.
"We need to play with more directness," Ancelotti said.
Real Sociedad coach David Moyes is looking to build momentum.
The Basque team, which beat Barcelona in the league last weekend, will next face Granada on Sunday. But that comes after a 1-0 loss to Villarreal in the Copa del Rey.
"(We need to) play better and especially defend better," Moyes said.