Messi had been on the receiving end of some fierce criticism in Spain as he failed to find the net as Barca slumped to three consecutive defeats in three different competitions over the past 10 days to all but end their chances of ending the season with a major trophy.

"Today Messi decided the game again," said the Spanish international.

"A lot of the time people demand too much of him. We need to leave him in peace and let him work."

A fourth straight defeat seemed on the cards when Aritz Aduriz put Athletic ahead five minutes into the second-half, but two goals in as many minutes sealed the points for Barca as Pedro Rodriguez tapped home from close range before Messi rifled in a free-kick from the edge of the area.

Victory moved Barca into second place, two points ahead of Real Madrid having played a game more, but still four points adrift of leaders Atletico Madrid with four games remaining.

Xavi, though, insisted they will fight until the end to try and defend their La Liga title in the hope that both Atletico and Real unexpectantly drop points before Barca host Atletico on the final day of the season.

"We knew how important today's game was, even though we don't have matters in our own hands. It is important to win and wait and see what happens.

"In general I think we played well both in attack and defence. To go out of the Champions League and lose the final of the Copa del Rey were two huge blows for the team, but we need to overcome them.

"Now we have to continue at the top of our game because this team still needs to fight."

Barca boss Gerardo Martino admitted to thinking it could have been another off day for his side in front of goal as they missed a host of chances before Pedro finally found a way through 18 minutes from time.

And Xavi hailed the character shown by his teammates to come from behind after he had been controversially replaced by Cesc Fabregas much to the displeasure of the Camp Nou crowd.

"We could have finished the game off long before because we had played well.

"It is important to win the three points and still be in with a chance in the league. In the end the team showed great courage. We found it difficult, but we showed great character."