Vegas Golden Knights forward Ryan Reaves was assessed a five-minute major for interference and a game misconduct after catching Washington Capitals forward Tom Wilson with a blindside hit late in the second period of Tuesday's game.
The force of the hit knocked Wilson's helmet off, which caused him to hit his head on the ice.
Wilson had to be assisted to the Capitals' dressing room and was ruled out for the remainder of the game with what the team called an upper-body injury.
Both Wilson and Reaves looked to be going at one another for the majority of the game, with each throwing hits at the other when given the opportunity.
Despite being at the center of suspension controversy this season, Wilson has been effective when in the lineup, tallying eight goals and 14 points in 11 games.