The Football Association has asked to see footage of a post-match scuffle between Manchester United players and Chelsea staff following their 2-1 defeat at Stamford Bridge on Saturday.
United lost the crunch title showdown at lunchtime before several players became embroiled in a bust-up with groundstaff and stewards in a warm-down session.
Patrice Evra, Gary Neville, Ji-Sung Park and Paul Scholes are believed to have been involved in the incident, which was sparked off when they were asked to move off the pitch by groundstaff.
"This will have nothing to do with the referee's report. He would have been in his dressing room a long way from the incident," said FA spokesman Andrin Cooper.
"But we will obviously be asking Chelsea to let us see their CCTV footage of the incident."
Both teams have already pledged to look into the incident which came soon after Chelsea had won following a controversial 86th minute Michael Ballack penalty.
Meanwhile, United defender Rio Ferdinand has apologised to a steward for kicking her by accident.
Ferdinand aimed a frustrated kick at a wall shortly after Ballack's penalty kick and also made contact with the steward.
"Unfortunately, a lady was stood by and I accidentally brushed her with my foot. I apologised profusely and went back to make sure she was okay," he said.
"I have arranged for a bouquet of flowers to be sent to her.
"Credit to her, she laughed it off and was very understanding. She said she wasn't hurt."