MADRID: Barcelona coach Ronald Koeman stared in disbelief from the bench.
Lionel Messi walked with his head down near midfield.
Defender Clément Lenglet batted the ball away with his hands in frustration after being called for a foul.
It was another frustrating night for Barcelona in the Spanish league.
Barcelona missed yet another chance to reach the top after blowing a two-goal lead in a 3-3 draw at Levante on Tuesday.
Barcelona was up 2-0 and 3-2 but couldn't hold on, despite knowing that a win would have put the team provisionally ahead of Atlético Madrid.
The draw left the Catalan club one point behind Atlético, which will host fifth-place Real Sociedad on Wednesday. Barcelona is one point ahead of defending champion Real Madrid, which visits 10th-place Granada on Thursday.
There will be two rounds remaining after the midweek matches.
"We have to wait and see what happens in the other games, but this was a huge step backward for us," Koeman said. "I don't know how to explain what happened. We played without intensity in the second half. To concede three goals in 45 minutes, it's just too much for this team."