This is another perfect example of why the National Hockey League needs to "not" ban fighting. First you have a punk like Toronto Maple Leafs forward Colby Armstrong, who has a history of being one of those players that plays on the edge and takes liberties on other teams star players.
If you think that I am kidding go over to Youtube you will see that he has a hit parade of high questionable hits on opposition players. [Example 1], [Example 2], [Example 3], [Example 4]... You can see a pattern here, always high, targets the head.
So fast forward to tonight, Armstrong hits Dennis Seidenberg a who is a European hockey player, that doesn't have a reputation of being a dirty player, and is not known for being a fighter, with a questionable hit, while Seidenberg is in a vulnerable position.
Armstrong is lucky that Seidenberg stepped in and that he didn't get beat up by Boston Bruins defenseman/bruiser Adam McQuaid, that would have been ugly...Per the hockey code the players settled this matter on the ice and there is no need to wait for the league office to act.