As the accompanying video explains:
It is important to note that there are many occasions during the course of a game where players use either their legs or their stick and upper body to restrain or impede opponents, or to gain leverage during a puck battle. When these players rise to the level of being illegal, the vast majority of them can be adequately punished with in-game penalties.
What causes this play to rise to the level of supplementary discipline, is Marchand’s use of both his upper and lower body to take Ekman-Larsson to the ice in a dangerous fashion and the speed at which the players are traveling towards the boards.
While the video includes reasoning on why it rises to the level of supplementary discipline, it’s Marchand’s lengthy history with the DoPS that makes it a three-game ban. The Bruins forward has been suspended six times in the past, including once for a slew foot in 2015.
Ekman-Larsson did not suffer a serious injury on the play. Marchand was also not penalized, but he will have to sit down for the Bruins next three games and forfeit more than $90K in salary.