Frustration from Crosby leads to a cheap shot on Pietrangelo.

The Pittsburgh Penguins faced off against the St. Louis Blues in their season opener on Wednesday night, and it became very apparent by the end of the second period that Penguins captain Sidney Crosby was struggling to control his emotions. 

After already finding himself in the penalty box multiple times, Crosby ended the second period with an ugly looking slash to the back of the leg of Blues captain Alex Pietrangelo, again a clear sign of his frustration. 

Now to be fair to Crosby, Pietrangelo had just given Crosby a shot of his own by delivering a short cross-check to the Penguins captain, but even with that in consideration the reaction from Crosby seemed over the top. 

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