Atletico Madrid could face UEFA action over the ugly scenes that occurred in their Champions League quarter-final with Manchester City on Wednesday.
Scuffles broke out late in the match and in the tunnel as Atletico’s frustrations at their failure to prise open City’s defence boiled over.
UEFA could appoint an ethics and disciplinary inspector to fully investigate what happened, and will await and assess reports on the trouble from the referee and match delegate.
City, protecting a 1-0 lead from last week’s first leg, withstood a barrage of pressure, intense provocation from a fired-up Atletico and a hostile atmosphere to reach the semi-finals after a hard-fought goalless draw.
The first major flashpoint came late in the game as a melee erupted after Felipe kicked City’s Phil Foden, whose head he had also bloodied in a poor earlier challenge.
Amongst the trouble Atletico defender Stefan Savic pulled unused City substitute Jack Grealish’s hair after the pair had exchanged words. Felipe was sent off for his involvement.
The problems continued after the teams left the field with players needing to be separated in the tunnel. TV footage showed objects being thrown and police reportedly became involved to restore order.
There were also suggestions City manager Pep Guardiola had liquid thrown at him as he headed towards the tunnel.
Guardiola later said he had “nothing to say” in relation to the trouble but did add that “everyone saw the action”.
Guardiola preferred to focus on his side’s rearguard action in the face of ferocious pressure.
City did hit the post through Ilkay Gundogan in the first half but spent most of the second period in a rearguard action as Atletico, criticised for their defensive attitude in the first leg, finally upped the tempo.
“We defended everything but they had the chances,” said Guardiola.
“They did everything. They know this competition and this stadium with their people. Always it is difficult.
“That is why it is a big compliment to the players because we have to live these kind of situations. We cannot expect every time, especially in the Champions League with the champions from Spain, we are going to make everything marvellous.
“You have to suffer. In part we suffered because we forgot to play but in part we suffered because the opponent was really good.
“When this happens you try to take the ball but you are not able. With the people and chances they had we had no chances to score a goal.”
Victory in the bruising tie could also have come at a cost. As well as Foden needing to play with a bandaged head, Kevin De Bruyne and Kyle Walker were both taken off after knocks.
City, who are chasing a treble this season, are back in action against Liverpool in the FA Cup semi-finals on Saturday.
“We are in big trouble,” Guardiola said on BT Sport. “We cannot forget we played three days ago a tough game against Liverpool. We came here, we have a lot of injuries.
“I don’t know what will happen in the next weeks but today we are going to celebrate.”
Action by UEFA would come just days after Atletico were hit with a partial stadium closure for the second leg against City for the “discriminatory behaviour” of their fans during the game in Manchester last week.
That punishment was suspended just hours before the match on Wednesday following an appeal to the Court of Arbitration for Sport.