Chelsea forward Nicolas Jackson was filmed throwing a strop after the final whistle against Tottenham while the rest of his team-mates were celebrating with the away fans.
The Blues came from two goals down to earn a thrilling 4-3 victory, with Jadon Sancho and Enzo Fernandez finding the net and Cole Palmer scoring twice from the penalty spot.
The result saw Chelsea move to within four points of Premier League leaders Liverpool, who have a game in hand. The west Londoners also pulled two points clear of Arsenal after they dropped points at Fulham.
After the final whistle, there were joyous scenes as the Chelsea players wandered over to the away fans to celebrate their victory. Jackson, however, lagged behind the rest of his team-mates and did not look as enthusiastic.
The 23-year-old trudged over with his head bowed, pulling a snood and the hood of his puffer jacket over his face. Chelsea boss Enzo Maresca ran over to greet Jackson after noticing that he was seemingly refusing to join the celebrations.
They shared a handshake before Maresca put his arm around Jackson and said something to him while covering his mouth with his hand.
The forward appeared to have been frustrated after being substituted in the 76th minute, with Christopher Nkunku coming on to replace him.
His indifference to the post-match celebrations did little to dampen Chelsea's spirits after securing their fourth straight Premier League victory, putting them firmly in the title race with Manchester City and Arsenal floundering.
Reflecting on the result in his post-match press conference, Maresca said: "This for sure is an important win, first of all for the way that it arrives.
"To come into this stadium, against this team and to concede two goals but to continue with the same plan on the ball, off the ball, it shows how the players are in this moment mentally strong. This is important.
"Since we start, we are trying to work the way we want to play on and off the ball, but also we are trying to work in terms of mentality and togetherness.
"To come into this season to think you are going to win or compete without suffering or without some bad moments is impossible. We were ready for that. It is probably too much after 15 minutes to give away two goals but it is the perfect win probably because of this."