wild/nhl

Ottawa Senators (7-5-2) at Toronto Maple Leafs (8-6-0), 7 p.m.

(Sports Network) - The Ottawa Senators already faced a tough task offensively without center Jason Spezza, so the loss of defenseman Erik Karlsson will certainly be felt two-fold.

The Sens try to shake out of a recent slump without their star blueliner on Saturday evening as they battle the Toronto Maple Leafs.

Spezza hasn't played for Ottawa since Jan. 27 due to surgery for a herniated disk that has him sidelined indefinitely but hopeful he can return this season. That won't be the case for Karlsson, who is expected to miss 3-to-4 months after surgery to repair a 70-percent cut of his left Achilles tendon suffered on Wednesday in a 4-2 loss to Pittsburgh.

Karlsson sustained the injury late in the second period after he and Pittsburgh's Matt Cooke met along the boards while chasing down a puck. Cooke's left skate appeared to graze Karlsson near the left ankle and the reigning Norris Trophy winner had to be helped off the ice as he was unable to put any pressure on his leg.

The 22-year-old had a team-high six goals with four assists in 14 games this season.

"The injury is unfortunate that it happened on a nothing play," said Ottawa head coach Paul MacLean. "It could have been potentially whistled down and we all know who was involved in it and that's just the way it is. Injuries are a part of the game."

Though Cooke has built a reputation for dirty play over his career, he wasn't penalized on the play and wasn't subject to any further discipline, with Senators general manager Bryan Murray saying the league suggested it was a hockey play gone bad.

Not only did Ottawa lose Karlsson, but Wednesday's defeat was its fifth in the past seven games. The Sens won their first two games without Spezza prior this current seven-game stretch.

Craig Anderson made 26 saves versus the Penguins and will be counted on heavily to help the Sens overcome the loss of Karlsson, who Murray said is a player that can't be replaced.

"We hope that other people eat up his minutes and defensively, we just won't allow any goals. I guess that's the only way you can do it," the general manager added. "Craig Anderson's got to be great, our defense has to be great and hopefully we'll find by committee a way to score goals."

Forward Milan Michalek also missed Wednesday's game with a knee injury and won't play Saturday. In response, the Senators added a trio of players to the roster on Friday, recalling forwards David Dziurzynski and Derek Grant as well as defenseman Eric Gryba from the AHL.

The Senators won't expect any sympathy from the Maple Leafs, who had a four- game winning streak snapped on Thursday with a 3-1 setback to the hosting Carolina Hurricanes.

Nazem Kadri scored his fourth goal of the season, his team-leading 12th point, while Ben Scrivens made 30 saves.

"It's easy sometimes to take it easy when you're on a streak and that's kind of what happened to us today," said Kadri. "It's upsetting because we know we can play better than what we showed here."

The Leafs and Sens are meeting for the first time this season after splitting six encounters in 2011-12, though Ottawa has won four of its past five in Toronto.