Rio Ferdinand may face action for his sarcastic applause of the referee Cuneyt Cakir following the end of Manchester United's 2-1 defeat to Real Madrid after the Turkish official had sent off Nani.
Uefa will wait to see if Cakir or the match delegate include the incident in their reports on the game and then decide what, if any action, may be taken. There is a 48-hour deadline for the files to be lodged with the governing body.
Cakir ruled that the winger's 59th-minute high challenge on Alvaro Arbeloa, in which he seemed to touch the ball first before landing a boot in the full-back's ribs, was a red-card offence.
Roy Keane, the former United captain, insisted the decision was correct in his role as a pundit for ITV. He said: "I think the referee has actually made the right call. Everyone's upset about it and it's slightly unlucky, but it's dangerous play. Whether he meant it or not is irrelevant. It's dangerous play – it's a red card.
"You have to be aware of other players on the pitch. Does he [Nani] think he's going to have 20 yards to himself? It doesn't matter if he knows there's somebody there or not, it's irrelevant. I don't think the referee actually made the decision because he waited a couple of minutes while the player was getting treatment. I think it might have been the assistant that made the decision, and I actually think he's made the right call. Any time I was sent off in my career I always thought: 'Did I give the referee chance to send me off?' And if the answer is 'yes', then it's out of your hands."
He added: "Whether it's [a brave decision] or not, it's the right decision. Whether he meant it or not doesn't matter. Nani's a quick boy to go down anyway. He's not the bravest player on the planet."
Gary Neville, another former United captain, was shocked by the decision. He tweeted: "Been going to OT since age of 5 and I've never seen the whole ground as in disbelief as they were last night at a decision! Nani is a player who regularly tries to control a pass like this over his shoulder and its never a red card! Changed the whole game! Poor ref. The crowd actually weren't angry/weren't shouting they were just open mouthed and in shock!"
Neville questioned why Real's goalkeeper, Diego López, was not also sent off for a first-half challenge on Nemanja Vidic at a corner. "The Madrid keeper on Vidic looked a similar type of incident. Anyway it won't be the first time or last! Just ruined a fascinating match and didn't feel right to Utd or Madrid people in the stadium!"