While Erik Karlsson's slashed Achilles tendon has Ottawa Senators fans in mourning, Canes defenseman Joe Corvo says he expects Karlsson to return to his fast-skating, dynamic defensive form. Corvo ought to know. He's had the same injury. In a November 2009 game against the Washington Capitals, Corvo was cut on the lower right leg by the skate of Caps defenseman Karl Alzner. Corvo said his Achilles tendon received a 75-cut sever. Alzner's skate also sliced into a nerve and Corvo's calf muscle. "It's pretty tough," Corvo said Friday of the rehab required from such an injury. "Your calf, I don't think, fully recovers, certain muscles. I think you end up compensating with other muscles. It takes a long time to get the strength back -- six to eight months. It's possibly a year to get as close back to normal as possible." Karlsson, last year's Norris Trophy winner, was injured Wednesday after a collision with Matt Cooke of the Pittsburgh Penguins. Cooke checked Karlsson into the boards, his left skate then catching Karlsson on the back of his left leg just above the skate, causing a 70-percent cut of Karlsson's Achilles tendon. Karlsson was not wearing cut-proof socks.