UEFA will study video evidence before deciding whether to take action against Wayne Rooney for a controversial challenge on Aalborg's Kasper Risgard on Wednesday night.
The Danish midfielder accused Rooney of "jumping at my chest" in a tackle that left "big marks" on his body during the 2-2 Champions League draw at Old Trafford. The incident went unpunished by French referee Laurent Duhamel but Risgard revealed Rooney had apologised to him after the game.
A UEFA spokesperson said: "We are aware of the incident and the disciplinary panel will study the footage and newspaper reports before deciding whether to take action."
Any retrospective action could lead to United striker Rooney being suspended for part of the knockout stages of the competition.
United had already secured their place in the last 16 before Wednesday night's contest but the result confirmed their place at group winners.
Risgard felt Rooney should have been sent off and accused Duhamel of being swayed by the home crowd in failing to do so.
He said: "I do not know what happened and why it happened, he (Rooney) was jumping at my chest.
"Maybe he was a little bit frustrated but Manchester United were playing some good football. It was still 1-1.
"I do not think the referee saw it. Anywhere else but this place it would have been a red card.
"These challenges happen in football - I have some big marks - but I do think it looks good on television. He did come and apologise to me after the game."
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