Tottenham midfielder Eric Dier confronted a fan in the stands after his club's FA Cup loss to Norwich City on Wednesday.
Dier appeared to get into a heated argument as stadium officials tried to break up the incident.
Spurs manager Jose Mourinho said after his team's penalty-shootout loss that the incident was a result of a fan insulting Dier's brother.
“I think Eric Dier did something that we professionals, we cannot do, but in these circumstances, I think every one of us will do,” Mourinho said. “Because when somebody insults you and your family is there and your family gets involved with the person insulting you, in this case a younger brother, I think Eric did what we professionals we cannot do.