Jose Mourinho has been asked by the Football Association to explain comments he made to the media ahead of the Manchester derby.
The FA has already asked both clubs for their observations regarding that incident, which reportedly saw Mourinho splashed with milk.
However, Mourinho may also find himself in hot water for comments he made prior to the match, when he appeared to accuse City of gamesmanship, saying: "A little bit of wind and they fall."
Mourinho also hit out at City's use of "tactical fouls" to break down play as he cranked up mind games with old rival Pep Guardiola heading into the derby.
An FA statement read: "The FA has requested observations from Jose Mourinho for pre-match media comments he made on Friday 8 December, prior to last Sunday’s match against Manchester City.
"He has until 6pm on Monday 18 December to respond."
City triumphed thanks to goals from David Silva and Nicolas Otamendi to move 11 points clear at the top of the Premier League.
But both clubs could be trouble with the FA after post-match clashes in the tunnel reportedly saw punches thrown by players.
Mourinho was said to have approached the City dressing room, unhappy with loud music being played after Guardiola's side came out on top.
"The only thing I can say is it was just a question of diversity; diversity in behaviours, diversity in education," Mourinho told reporters when asked about the incident.
"Nothing more than that. That's all I'm going to say."
City and United have been given until 18:00 GMT on Friday to provide their observations to the FA regarding the incident.