At 9:35 of the second period, the Flames' leading scorer challenged Allen to a fight in retaliation for Allen's heavy hit on Chuck Kobasew earlier in the game that knocked the Flames forward from the game.
It was a spirited fight that ended up with Iginla on top of Allen. Nothing appeared wrong initially as Iginla served his fighting major. However, upon exiting the penalty box, Iginla went to the Flames' dressing room.
Iginla has been one of the league's hottest players of late. He was named the NHL's first star for December after racking up 10 goals and 16 assists.
Iginla entered the night fourth in the NHL in scoring with 22 goals and 30 assists.
He scored his 23rd goal in the first period, deflecting in defenceman Dion Phaneuf's shot from the blue-line.