Eric Dier appeared to jump into the stands to confront angry supporters after Tottenham were knocked out of the FA Cup by Norwich City.
Spurs lost to their Premier League opponents on penalties, after a rather dull 90 minutes that finished 1-1.
Jan Vertonghen had opened the scoring in the first half before Josip Drmic equalised with 12 minutes to play.
After being dumped out of the cup by 'lesser' opposition at home, it seems tempers were flaring in the stands at full-time and Dier went in to confront some fans.
Check out the extraordinary footage and photos below:
Unbelievable, have you ever seen anything like it?
It's not yet confirmed what exactly Dier was reacting to, with reports differing at this moment in time.
Spurs manager Jose Mourinho did speak about the incident after the match.
"I don’t think that belongs to the game," he said during the post-match press conference.
"The game was a fantastic representation of the FA Cup, but I cannot run away from the question.
"I think Eric Dier did what we as professionals cannot do but when someone insults you and your family is involved, especially your young brother."
"This person insulted Eric, the younger brother was not happy with the situation and Eric was not happy. We as professionals cannot do what he did."
While it was a very disappointing night for Spurs, both on and off the pitch, Norwich booked their place in the last eight of the FA Cup.
The Canaries will play at home against either Derby County or Manchester United later this month.
But Wednesday's result will be overshadowed by the shocking incident involving Dier at the final whistle.
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