Victor Valdes has declared that Barcelona need to take maximum points from their remaining 18 matches in order to win La Liga. A goalless draw at Villarreal on Saturday left Pep Guardiola’s team seven points behind leaders Real Madrid, who recovered an early deficit to beat Zaragoza 3-1. \"We dropped two crucial points against Villarreal,” Valdes told Sport. “We simply have no more room for error. We have to win every point that is available to us. That’s the size of our task. If we want to fight for the title, we can’t slip up any more because there is a very strong rival above us.” Barcelona, who have a small squad, have been affected by injuries in recent months. Forward David Villa was ruled out for the rest of the season after breaking his leg in their 4-0 win over Al-Sadd in the semi-finals of December’s FIFA Club World Cup, which the Catalans went on to win, while influential playmaker Andres Iniesta recently joined him on the sidelines, though he is expected to return to action in the first half of next month. Furthermore, the in-form Alexis Sanchez took a knock to his shoulder which left him unable to start the defeat at El Madrigal. Having drawn six and lost one of their 20 league games, Barça have already dropped the same number as they did in the entire 2009/10 campaign and just three less than they did last season. However, Valdes has refused to blame this on the squad’s casualties. \"Injuries can never be used as an excuse,” stressed the 30-year-old goalkeeper, who was born in Catalonia and emerged from La Masia. “Only small clubs can use them. There is enough strength in depth to deal with all the fixtures. \"I have the feeling that we are tired. But we are facing opponents who are also playing a lot, and nobody here ever said that this would be easy. I can’t really say exactly what is happening. The important thing is that the team is working hard, but we must continue giving our all - and even more if necessary.\" Barcelona return to action at home to mid-table Real Sociedad on Saturday, while Real Madrid are at eight-placed local rivals Getafe.