Madrid: League leaders Barcelona look for a third league win in a week as they host strugglers Real Zaragoza at Camp Nou on Saturday.

Barceona needed a late goal from top-scorer Lionel Messi, who has 27 league goals, to seal a vital 1-0 win at Valencia on Wednesday and the champions are keen to maintain their seven point lead over second-placed Real Madrid.

"The Valencia win was a very important result. Points like these are what could win us the title," said Barcelona midfielder Xavi.

"There are still some difficult games to play. There’s a lot at stake. But we’re optimistic. We are pleased with the team dynamic, the way we’re playing and the attitude."

Spanish international Xavi returned from a calf injury against Valencia but Barcelona are still without goalkeeper Victor Valdes and captain Carles Puyol who are both doubtful for next Tuesday's Champions League second leg at home to Arsenal.

After difficult away matches at Real Mallorca and Valencia, Barcelona will be glad to be back at home although Zaragoza, two points above the relegation zone, are on a high after a 2-1 win at Athletic Bilbao on Wednesday.

Real Madrid closed back to within seven points of Barcelona with an emphatic 7-0 home win over Malaga on Thursday to maintain their 100 percent home record.

Cristiano Ronaldo scored a hat-trick in Madrid's biggest win of the season and coach Jose Mourinho will hope his side can now improve on their erratic away form - they have dropped 14 points on the road - in Sundays trip to Racing Santander.

Racing are unbeaten in their last five league outings under new coach Marcelino and they have only lost twice at home this season.

Elsewhere Valencia are at Real Mallorca as they battle to hold onto third and the final automatic Champions League place.

The 1-0 defeat to Barcelona was their first in the league in 2011 and Villarreal are now just a point behind in fourth.

"We are hurting after the Barcelona defeat but we competed with the best team in the world," said Valencia coach Emery.

Villarreal closed to within one point of Valencia and hope to stay on their heels with a win at Atletico Madrid on Saturday.

Villarreal have been poor on their travels with just four away wins and Atletico will be full of motivation having moved to within three points of the top six.

"It is a special game because there is a really good atmosphere at the (Vincente) Calderon," said Villarreal midfielder Borja Valero. "For us finishing third would be the best we could do in the league and the club would have guaranteed revenue (from the Champions League)."

European rivals Athletic Bilbao and Sevilla lock horns at San Mames on Sunday as the race for the European places hots up.

Bilbao have lost their last four matches but are clinging to sixth place with Sevilla level on 38 points.

"When you can't win you have to at least get a point," said Bilbao midfielder Carlos Gurpegui. "When you lose everything looks bad. Sunday is a huge game for us against a direct rival. We are in a good position in the league but we have to try and win against Sevilla."

Down at the bottom relegation rivals Hercules and Almeria face off on Saturday in a crucial six-pointer.

"Not scoring goals is certainly complicating things for us at the moment," said Hercules coach Esteban Vigo.

Hercules have failed to score in their last three outings and are one point above the relegation zone, while Almeria prop up the 20-strong table.

In other matches, surprise package Real Sociedad travel to Deportivo La Coruna on Monday.

Sociedad won the second division last season and have enjoyed a sensational return to the top-flight so far lying just three points off the top six.

Fixtures
Saturday
Real Mallorca v Valencia (1700 GMT), Barcelona v Real Zaragoza (1900 GMT), Atletico Madrid v Villarreal (2100 GMT)
Sunday - all 1600 GMT unless stated
Sporting Gijon v Getafe, Hercules v Almeria, Malaga v Osasuna, Levante v Espanyol, Athletic Bilbao v Sevilla (1800 GMT), Racing Santander v Real Madrid (2000 GMT)
Monday
Deportivo La Coruna v Real Sociedad (2000 GMT)