Barcelona must "turn the page" and ensure their Champions League disappointment does not cost them success in the Primera Division and Copa del Rey, according to playmaker Andres Iniesta.
The defending champions were knocked out in the quarter-finals of Europe's premier club competition this week by Atletico Madrid, who are also breathing down Barca's necks in the league.
It was a third defeat in four games for Luis Enrique's men and the worry for them is their slump has come at just the wrong time, with only six league games and a Copa del Rey final against Sevilla to come.
Having looked nailed on for another league title, Barca have picked up only one point from their last three games, losing successive matches against Real Madrid and Real Sociedad.
The gap to Atletico is now only three points, with Real a further point behind.
Iniesta said on the club website: "We're not in very positive form. We have to find strength from somewhere because what we still have to play for is very nice too.
"Difficult times like this always generate doubts but we have to turn the page and focus on what we have left."
Valencia are the visitors to the Nou Camp on Sunday and they will hope to build on last weekend's victory over Sevilla, which ended a run of four straight league defeats.
Coach Pako Ayestaran said on the club website: "(Facing Barcelona is) always an opportunity, not a risk.
"The mental factor always has an influence. With FC Barcelona it is always complicated, it is important that we continue to grow from the line we have marked.
"I see the team focused, wanting to improve. We have a responsibility to be able to implement what we do in training."
Valencia will be without winger Sofiane Feghouli, who has been suspended by the club until April 21.
The club did not give a reason for opening disciplinary proceedings but, according to reports, Feghouli refused to take part in a warm-down session following the victory over Sevilla.
Atletico take on Granada in a match of significance at both ends of the table, while Real will have the chance to put pressure on the teams above them when they face another struggler, Getafe, on Saturday.
Midfielder Casemiro said on realmadrid.com: "We know that winning La Liga is going to be a little bit tough, we've got a tricky away game at the weekend and we need to give our best in all of the games."
Villarreal appear destined to finish fourth and will hope to end a week in which they reached the Europa League semi-finals by defeating Rayo Vallecano on Sunday.
Fifth-placed Celta Vigo face Real Betis on Saturday while fellow European challengers Athletic Bilbao and Sevilla meet Malaga and Deportivo La Coruna respectively.
In other matches, relegation-threatened Sporting Gijon travel to Las Palmas and Eibar host Real Sociedad.
Source: PA-WIRE
