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 spent a long summer thinking about that playoff series and what could have been. [The Blackhawks] ended up being the Stanley Cup champions, so we know we lost to a very good team. It's tough to know how close we were, and it motivates us for this year.
— Nashville captain Shea Weber in an interview with the Predators website