Despite defeat at Old Trafford on Saturday, the Spanish defender is confident that improvement in the club's home form is key.
"We lost but the truth is that we have to win more games at home," he said. "We are still in the race to be in the Champions League next season.
"It's hard but Chelsea and Arsenal have lost many points too. Chelsea lost this weekend and we can't forget Newcastle.
"It's really important that we have to play these teams at home and we'll have another man - you play with 12 with our fans."
"It is hard to beat Manchester United at home but against teams like Blackburn and Swansea at home we need to win the points.
"There are many games left and we have to beat many teams to try and be there.
"You never know in football - that's why everyone likes it. But we're still in the race."