Manchester United manager Erik ten Hag says it was "unacceptable" for Marcus Rashford to go to a nightclub party after the team's humiliating 3-0 derby defeat at home to Manchester City on Sunday.
Reports emerged the day after the match that the England international, who turned 26 on Tuesday, had gone to a nightclub in Manchester for a pre-arranged birthday party hours after the Old Trafford loss in the Premier League.
Rashford plundered 30 goals for United last season and signed a new five-year deal with the club over the summer, but has struggled this season with one goal in 14 appearances.
"Yes, I am aware of it," Ten Hag said on Friday.
"I spoke with him about it. It's unacceptable, I told him, he apologized and that's it. For the rest it's an internal matter."
Ten Hag repeated it was an "internal matter" when asked if Rashford had been fined for an incident that he says will not impact the forward's availability for Saturday's crunch Premier League trip to Fulham.
Eighth-place United has lost five of its 10 league games this season.