In spite of having a previous record of suspensions after Pacioretty's head hit on Kris Letang last year, the NHL's division player safety and Brendan Shanahan made the right call today instead of the easy call.
We've analysed the video pretty in depth in the comments section of various posts today, and concluded that Pacioretty probably didn't deserve to get suspended, and according to Nick Kypreos, Shanahan felt the same way:
This is great news for the Habs, who already have Rene Bourque out with an illness on the left side. It could have been quite the loss if Bourque was out multiple games, as Travis Moen would likely be in the top six.
It's unknown as of yet whether or not the NHL will release a detailed reason why they felt Pacioretty wasn't deserving of discipline, but I'm guessing it has a lot to do with McDonagh cutting into Pacioretty's path at the last second.
Expect some angry, angry Rangers fans.