Now we know why the Rangers' number 10 did it. The Bruins' little pest reportedly made comments related to Panarin's nationality, adding that no one liked him here. He also mentioned Russian President Vladimir Putin in his comments. Remember that Panarin had been very critical of Putin in the past and his comments caused quite a stir.
Anyway, coming from Brad Marchand, this is not really surprising. There is a long history of similar events. We only have to think of the time Marchand literally licked Ryan Callahan during the 2018 playoffs. The Bruins' little pest will never change!