Arsenal defender Gabriel was spotted laughing in the face of Manchester City striker Erling Haaland after his side took an early lead in Sunday's grudge match.
The Gunners went 1-0 up at the Emirates Stadium in only the second minute courtesy of Martin Odegaard's third goal of the season.
After seeing the ball hit the back of City's net, Gabriel gleefully ran up the pitch to celebrate with his team-mates, pausing along the way to mock Haaland.
Sunday's game was the first meeting between City and Arsenal since their bad-tempered 2-2 draw at the Emirates Stadium in September.