Barcelona were angered that a goal scored by Zlatan Ibrahimovic, which was clearly offside, was not ruled out. They were also made to play with nine men just before the goal.
“The club has written to Uefa due to a series of incidents on the pitch in the understanding that objectively speaking it was evident that the referee did not apply the rules of the game,” Barcelona’s spokesman, Toni Freixa, said.
“When two players from the same team are on the floor the referee should stop the match, which did not happen. What’s more he then obliged them to leave the pitch, in contravention of the rules.
“It is an incident that is sufficiently serious in a competition like the Champions League to bring to Uefa’s attention so that it does not happen again.”