Scott McDonald has apologised to Gordon Strachan and his Celtic team-mates for his petulance.
The Australian striker threw his tracksuit top away and kicked a seat in the dug-out after being substituted in the 1-0 defeat to Motherwell at Parkhead.
A chorus of boos rang out as the board went up signalling Georgios Samaras' introduction in place of the 26-goal man, but McDonald has refused to defend his actions.
Instead the frontman has backed his boss as the Hoops look to try and retain their Scottish Premier League crown.
"It was nothing to do with the team or the gaffer, it was just my passion for playing for the club," McDonald said. "I wanted to stay out and try and turn the game around for the team and myself, but he made the decision for the team and I've got to understand that.
"My response created a negative reaction around the stadium and that was incorrect of me. I apologised to my team-mates and manager straight after the incident and then again when we went in to the changing room.
"No player should do that and I'm fully aware of that. I'm 150 per cent behind my manager and everyone at the club.
"Credit to the gaffer and the way he dealt with it. We continue to work together and we go forward from there."