From another angle, we can clearly see that Bennett landed a sucker punch on Marchand:
"Sam Bennett throwing a little rabbit punch at Brad Marchand during last night's Game 3 between the Panthers and Bruins.
Another really bad look for a Panthers forward."
In an update from today's morning skate, we learned that Marchand wasn't on the ice with his teammates:
"Brad Marchand not on the ice for Bruins practice this morning after taking the Sam Bennett sneaky punch to the head in the first period last night."
If Marchand ends up missing games in the series against the Panthers, it could be a potential disaster for the Bruins. While he failed to score a goals since the second round started, he still brings a lot of energy to his teammates.
We should get an update from both the Bruins and the NHL about Marchand's health and Bennett's fate before the pick drops on game 4, on Sunday night.