In a nightmare scenario for the Ottawa Senators, Erik Karlsson had to be helped off the ice late in the second period versus the Pittsburgh Penguins after Matt Cooke appeared to step on the back of his leg during a hit along the boards.

It's pretty much never good news when you can hear the player scream chillingly after the collision. Hopefully, for Senators fans, this one is an exception.

It goes without saying that Karlsson is one of Ottawa's most important players. Coming into Wednesday night, he had 6 goals in 13 games, tops among defencemen, and was averaging 27:52 a night, second only to Jack Johnson in Columbus.

Karlsson also leads the NHL in shots on goal with 62. Johnson is second among defencemen in this category at 36. Again: 36.