Barcelona forward, Lionel Messi, has said they will not win the Champions League, if they don't improve their performances.
Messi was speaking after a 2-1 loss to Osasuna, which saw Real Madrid crowned LaLiga champions on Thursday.
Barca could still avoid their first trophyless season since 2007/2008, if they win the Champions League which resumes next month.
The Catalans drew 1-1 with Napoli in the first leg of their last-16 tie and host the Serie A club on August 8.
"I said it before that if we continued playing as we were, it would be difficult to win the Champions League and now it's clear it wasn't even enough to win La Liga.
"We have to change a lot because if we don't, we will lose against Napoli as well. We need a little time to clear our heads and then to think about the Champions League, which starts from zero," Messi said.