PITTSBURGH -- The Ottawa Senators fell 4-2 to the Pittsburgh Penguins on Wednesday, but the defeat could be even more costly, as they also lost Norris Trophy winner Erik Karlsson indefinitely.
Karlsson sustained a laceration to his left Achilles tendon and will require surgery. He was cut by the skate of Penguins left wing Matt Cooke as they scrapped for the puck along the boards. Late in the second period, Cook's skate blade came down above the top of Karlsson's boot.
The Senators (7-5-2) were clearly concerned about their fallen teammate.
"Obviously the way he's playing and how much (Karlsson) means for us, for our team, it feels terrible and I feel really bad for him," Senators' captain Daniel Alfredsson said.
The Penguins (9-5), meanwhile, were pushed to victory by three-point efforts from James Neal and Sidney Crosby, while Marc-Andre Fleury made 27 saves.
The Penguins broke the stalemate when Pascal Dupuis swept Crosby's pass into the net past a sprawling Craig Anderson for his fifth goal of the season at 16:23 of the first.
In the second, the Senators evened the game and then took the lead within 24 seconds.
The first of those goals came at 10:31 when Stephane Da Costa got his first of the season by banking a rebound off the backside of Marc-Andre Fleury.
Ottawa's second goal came off the stick of Jim O'Brien when he fired a hard wrist shot that handcuffed Fleury, deflecting off his glove and into the net. It was O'Brien's fourth of the season.
"I was definitely not happy with giving up two so quick, but I knew if I made some key saves for the guys they would get them back," Fleury said.
The Penguins would eventually get them back.
Pittsburgh tied the game, 2-2, on a power play goal at 13:47 of the second when a wide-open James Neal took Crosby's pass and wristed in his ninth of the season over Anderson's glove.
"I've often said if you're going to make a book on a shooter and a guy getting open, just watch this guy play the game," Penguins' coach Dan Bylsma said. "Both five-on-five and the power play."
Crosby recorded his 400th career assist on the goal and it also marked the sixth consecutive game in which the Penguins recorded a power play goal.
"I think in the course of the game their power play was better than ours," Senators' coach Paul MacLean said.
The Penguins retook the lead 1:52 into the third when Neal tapped in his second goal of the game from right on the doorstep.
Crosby notched his sixth goal of the season at 11:42 of the third as the result of some brilliant passing just as a Penguins power play had expired.
The Penguins were able to put up four goals on Anderson, despite his lead-leading .956 save percentage heading into Wednesday's game.
"We definitely got him moving from post to post a bit," Crosby said. "We try not to change a whole lot, what we do is what we do. Hopefully, every game we can score on whoever's in net."
NOTES: Before the game, Pittsburgh traded winger Eric Tangradi to Winnipeg for a seventh-round pick in the 2013 NHL Draft. In parts of four seasons with the Penguins, Tangradi recorded one goal and four assists in 45 games. ... Pittsburgh defensemen Kris Letang and Matt Niskanen were both in the lineup for the first time after extended absences due to injury. ... G Craig Anderson has started all but two of Ottawa's 14 games. ... Pittsburgh C Brandon Sutter appeared in his 300th NHL game. ... Ottawa completed its third set of eight back-to-back games. ... C Dustin Jeffrey and D Robert Bortuzzo were healthy scratches for Pittsburgh. LW Milan Michalek (lower body) was scratched for Ottawa. ... Pittsburgh next plays at Winnipeg on Friday night, while Ottawa will travel to Toronto on Saturday.