Espanyol and Athletic Bilbao are both looking for wins to leap into the Spanish league's Champions League places this weekend and overtake struggling Levante, which visits leader Real Madrid.
Levante was the early season surprise but its grip on fourth place has slackened after six league games without a victory. It is now tied on points with Espanyol and only two above Bilbao, which has lost just once in 13 matches overall ahead of Saturday's match at Real Betis.
Bilbao reached its 36th Copa del Rey final on Tuesday following an emphatic victory over third-tier club Mirandes. With striker Fernando Llorente in tremendous form, the all-Basque squad coached by Marcelo Bielsa has a strong chance of playing in Europe's top-tier competition next season.
Llorente has scored 11 goals since returning from injury last month to lead a young squad full of budding Spain internationals, with Llorente and Javi Martinez already fixtures in the squad that won the World Cup.
Espanyol has brushed off injuries to forwards Alvaro Vazquez and Sergio Garcia to be unbeaten in seven league matches ahead of last-place Zaragoza's visit on Sunday.
"The second half of the season is always the most difficult, you have to manage situations of utmost stress," said Espanyol coach Mauricio Pochettino, whose team tailed off in the second half of last season. "We know any first-division team is capable of beating another. We've got great respect for (Zaragoza) as they are in a situation we have been through."
Zaragoza has only 12 points from 21 games this season to sit 11 points from safety. Last weekend's 2-1 home loss to Rayo Vallecano - when it surrendered a 1-0 lead - showed little indication the club is capable of staying up.
Levante was expected to be battling to stay up but a tremendous start put it top of the league for several rounds. The remains winless in 2012 before a trip to the Santiago Bernabeu, where Madrid has won nine of 10 games and its loss only to Barcelona.
Madrid could have Argentina forward Angel di Maria back from injury, but midfielder Sami Khedira remains out while utility player Hamit Altintop will be sidelined with a left leg injury.
Barcelona, meanwhile, is on the road at Osasuna on Saturday looking to pressure Madrid, which holds a seven-point advantage.
Barcelona beat Valencia 2-0 to secure its place in the cup final against Bilbao - also its 36th appearance - and can look forward to a league match with a much healthier squad, after Andres Iniesta and Alexis Sanchez returned from injury while Xavi Hernandez scored after being rested for two games.
Pedro Rodriguez and Sergio Busquets also trained with the rest of the team on Thursday.
"We're going to make sure the league is very long for Madrid," Barcelona defender Gerard Pique said on Thursday.
Third-place Valencia looks for its first league victory since December when it plays Sporting Gijon on Sunday, while new Sevilla coach Jose Miguel "Michel" Gonzalez begins with a match at Real Sociedad on Monday.
In other 22nd-round games, it's: Racing Santander vs. Atletico Madrid; Malaga vs. Mallorca; Rayo vs. Getafe and Villarreal vs. Granada.
AP