Marouane Fellaini could face a Uefa investigation after throwing an arm in the face of Emre Can that went unseen by officials during Manchester United's Europa League defeat to Liverpool.
Louis van Gaal's team were well beaten 2-0 by their rivals on Thursday night, Daniel Sturridge and Roberto Firmino giving the Reds a commanding lead ahead of the second leg at Old Trafford next week.
But Manchester United could be without Fellaini in that game, if Uefa decide to look at footage of an incident that occured late in the match at Anfield.
Belgian midfielder Fellaini had words with Can and then threw an arm or even an elbow in the face of his opponenet.
The incident was missed by the six officials during the game, but former World Cup final referee Howard Webb told BT Sport he expects Uefa to look at the incident that definitely would have warranted a red card.
"To top off a bad night for Manchester United they might face the second leg without Marouane Fellaini," said Webb. "At the very end of the game he had words with Emre Can and ended up throwing a left arm in the face of Emre Can.
"If the referees had seen that it would have been a red card for sure and Uefa might want to have a little look at that as well, it's clearly an act of violent conduct and he's lucky that none of the six officials saw it on the day.
"It just sums up a bad night for Manchester United."
Speaking after the game, Van Gaal said he "hadn't seen that" in reference to the elbow, while Liverpool manager Jurgen Klopp admitted he saw the incident but didn't make any comment.
"There is nothing that I should say about the elbow but I saw it," said the German. "I am not the referee – you can write what you want but without anything from my side."
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