Messi was on target during the match with a brilliant free-kick to equalise but Roberto Torres won it late on for the 10-men of Osasuna.
The captain spoke about his team’s deficiencies after the game and called for change at the club if they are to have any chance of winning the Champions League.
“All season we have been a very weak team, beaten for intensity, for motivation, people can score against us very easy, we lost many points where we shouldnt lose them. This game has just summed up how our season has been,” he said.
“Fans must be very angry at how this whole season has gone, that is normal, we are too, its logical. Rome, Liverpool, people are running out of patience because we are not giving them anything
“If we want to fight for the Champions League we must change many things, do a lot of self-criticism. If we continue like this, we will lose the game against Napoli.”
Barcelona finish off their La Liga campaign on Sunday at Alaves and will then take a break before regrouping for their Champions League challenge.