Well, you can add Erik Karlsson to the list of Matt Cooke injuries. The Norris Trophy winner and star of the Ottawa Senators had to leave the ice on one skate after a collision with Cooke along the boards in the second period.
The injury occurred when Cooke laid a hit on Karlsson as the defenseman went to collect a puck near the corner boards. As the video above shows, it appears that while the hit itself wasn't dirty, Cooke seemed to bring his skate down hard on Karlsson's left ankle. Karlsson immediately fell to the ice, and when he attempted to get up and put pressure on his left foot he grimaced in pain and threw his stick.
Was Cooke deliberately attempting to injure Karlsson? Whether he was or not, this is horrible news for the Senators, who are already without Jason Spezza for an extended period of time and are awaiting news on Milan Michalek's injury earlier before the game.
UPDATE: The Senators have provided an update on Karlsson's injury:
Update on Karlsson: Erik suffered a laceration to his left achilles, which will require surgery to repair. He will be out indefinitely.— Ottawa Senators (@NHL_Sens) February 13, 2013