The leaders are looking for an eighth straight win since the top flight resumed on Friday, when they host Alaves at the Bernabeu.
Luis Suarez said Barcelona must be ready if La Liga leaders Real Madrid drop points as the title race nears its conclusion.
Two-time defending champions Barca kept their slim title hopes alive with a 1-0 victory over rivals Espanyol on Wednesday.
Suarez scored the only goal of the match in the 56th minute to relegate Espanyol midweek, while moving Barca to within a point of Madrid.
Madrid can restore their four-point advantage against Deportivo Alaves on Friday and while Barca only have three games remaining, star forward Suarez insisted the Catalan giants have to be ready to pounce on any slip-ups.
“What we have to do is win our next three games,” Suarez, who moved third on Barca’s list of all-time scorers, said afterwards. “Whatever Madrid do is up to them.
“If the rival drops points then fantastic, we have to think about being there if they do.”
Barca were far from their best at Camp Nou, where substitute Ansu Fati was sent off after coming on at the start of the second half, while Espanyol’s Pol Lozano was also dismissed.
But Barca managed to extend their unbeaten run to nine games following back-to-back triumphs.
Suarez added: “We knew it was going to be difficult. We knew their situation. We have to be aware of the fact that we put in a great performance on Sunday and were still feeling the consequences of that physically. The important thing is to win and to get three more points.
“I think if I didn’t score in the first half or Barcelona didn’t create more chances, that’s virtue of the rival, who were very well organised.
“I think they make it difficult for Nelson Semedo and Jordi Alba to push up on the flanks. But eventually the chance came and I’m delighted to be able to take it.
“I didn’t see Ansu Fati’s [red card] because there was a player in the way and the other one I didn’t see either, there was another rival blocking my view.
“But in both cases VAR – which is there to help in these kind of situations – was able to help the referee to take the right decisions.”
After his goalscoring display in the 4-1 rout of Villarreal on Sunday, Antoine Griezmann was handed another start alongside Suarez and Lionel Messi.
“It’s the manager who takes the decision,” Suarez said. “He wanted to find a formula, it’s the formula he’s trying at the moment. It’s the first year of Antoine here so we know it’s difficult – the adaptation period. The other day we could all enjoy a brilliant performance from Antoine Griezmann.”
Espanyol knew anything but a derby victory at Camp Nou on Wednesday would relegate them to the second tier for the first time since 1994 but they were unable to preserve their top-flight status.
“I think today’s match I’m proud of my team-mates, we had chances,” Javi Lopez said. “If I’m here now it’s to ask for forgiveness from our fans because we know these are tough moments for us but also for our fans. It’s been a season in which nothing has gone right for us.
“I thank the fans but apologise again because it’s the players’ fault. We apologise again and tell them we are committed to coming back stronger and will fight for this club badge. That’s all I’ve got to say – sorry to the fans, that’s the minimum we can do.
“I think we all assume the responsibility in the changing room. We’re most responsible for this. The players are out on the pitch and the ones who fault it is. These are really tough moments for all of us. We just have to be absolutely committed to come back stronger than ever before. I’m convinced that we will.”
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