Ottawa Senators defenseman Erik Karlsson will need surgery to repair his left Achilles after the tendon was cut by a skate blade late in the second period Wednesday night against host Pittsburgh.

The Norris Trophy winner last season as the NHL's top defenseman, Karlsson was cut by Penguins forward Matt Cooke's skate blade as the two tangled along the boards.

"Him and I were engaged and he went down screaming," said Cooke, who has been suspended several times for much-criticized hits, some of them involving head shots that injured opposing players. "I didn't even know what happened. It's a complete accident, and obviously I feel terrible about it. ... It's scary."

James Neal scored twice and Sidney Crosby had a goal and two assists to help the Penguins beat the Senators 4-2.

Blues 4, Red Wings 3: Alexander Steen stuffed in a rebound 52 seconds into overtime, lifting St. Louis to a victory over host Detroit.

St. Louis snapped a five-game losing streak that followed a 6-1 start. The Red Wings had won a season-high three straight, a stretch that started with a 5-1 victory over St. Louis.

Blues goaltender Jake Allen, making his first NHL start in his second game in the league, made 15 saves. Jaroslav Halak missed his fifth straight game with a groin strain.

Flames 7, Stars 4: Mike Cammalleri had three goals in his return from a hip injury to help host Calgary beat Dallas.

Blue Jackets: A little more than 24 hours after firing Scott Howson, the team announced the hiring of Jarmo Kekalainen of Finland as the first European to be a general manager in the NHL.

Kekalainen, 46, served as director of amateur scouting with the St. Louis Blues from 2002-10. Since then, he has been general manager of the Jokerit club in Helsinki.