Karlsson hasn't played since sustaining a 70-percent tear of the Achilles' tendon in his left leg when he was stepped on by the Pittsburgh Penguins' Matt Cooke during a game Feb. 13.
The 2012 Norris Trophy winner underwent surgery to repair the cut Feb. 14, and was expected to miss 3-4 months. He had 10 points in 14 games at the time of the injury, and was averaging 27:03 of ice time per game.
I remember the first time at Wrigley Field all of us had the long johns, the turtlenecks and the extra equipment because we were afraid of being cold. Halfway through the first period everybody's ripping everything off and we just ended up wearing what we would normally wear for a game at the United Center.
— Chicago Blackhawks forward Patrick Sharp on the 2009 Bridgestone NHL Winter Classic