Hansi Flick urged his Barcelona players not to get complacent in their final six games of the LaLiga season ahead of facing Mallorca on Tuesday.

Barcelona are four points clear at the summit of the standings, but were forced to dig deep to claim a 4-3 comeback victory over Celta Vigo in their last league encounter.

It was the second straight match that Barcelona had conceded three goals, having gone down 3-1 to Borussia Dortmund in the second leg of their Champions League quarter-final clash.

Real Madrid are hot on their heels in the table, leaving it late to earn a 1-0 win over Athletic Bilbao on Sunday thanks to Federico Valverde's stoppage-time winner.

"We must always improve. After Dortmund, after Celta, we have to do much better. We have the quality to beat anyone, but we have to do it well," Flick told reporters.

"The comeback against Celta, that positive energy, that's the state of mind we need.

"LaLiga has a high level and the objective is not to drop points, but it's not easy. We saw that against Celta.

"I hope it's a wake-up call. It's a long road. Madrid are fantastic, and they also want to achieve their objectives."

Barcelona welcome Mallorca to the Estadi Olimpic Lluis Companys in midweek, with the visitors eyeing a spot in Europe next season.

Mallorca have not beaten Barcelona in LaLiga since a 2-1 victory in May 2009, but Flick did not underestimate the challenge ahead of his team.

"Mallorca are having a very good season. They can go to Europe. It will be a tough game. They defend very well. They make good transitions," Flick said.

It has been suggested that Flick could look to rotate his squad on Tuesday, with one eye on their Copa del Rey final against Clasico rivals Madrid this weekend.

The Barcelona boss challenged some of his disgruntled fringe players to do their talking on the pitch if they are given the chance to do so.

Ansu Fati kicked a water cooler after not being brought on against Celta, while Hector Fort and Flick had a heated exchange on the pitch after the match.

"I understand that they are not happy. I was a player myself. Everyone wants to prove themselves and help the team," Flick said.

"I understand the feeling, but not the reaction. Victories have to be celebrated. The reaction has to be on the pitch, not off it."