CHICAGO (AP) -An impressive win for the Chicago Blackhawks could turn out to be a costly one.
Chicago's Cristobal Huet stopped 22 shots as the Blackhawks won their second straight. Chicago's Kris Versteeg, the NHL's rookie scoring leader, added two assists.
However, Blackhawks defenseman Duncan Keith left the game with an undisclosed injury after taking a hard, open-ice hit to the shoulder and head area from Buffalo's Drew Stafford midway through the second period.
Keith, who was hit just after releasing a shot, entered the game averaging nearly 26 minutes of ice time.
Keith is the anchor of the Blackhawks' defense. He leads the team in ice time and plus/minus at plus-23.
In 41 games, Keith has six goals and 21 assists, including an assist in the first period on Wednesday. He has 16 points in his past 17 games.
The Blackhawks weren't sure how serious Keith's injury might be.
"Dunc was talking after the game," Chicago coach Joel Quenneville said. "We'll have a better idea tomorrow."
Keith had a hard time getting to his feet after the hit, but may have been dazed and not suffered a more serious injury.
"As far as I know, he's in good spirits," Toews said. "He's chatting away and is his normal self. I guess we'll wait and see what the doctors say."
Stafford, who has 10 penalty minutes, said his hit was a matter of hard back-checking, not an intent to injure.
"I hope he's OK. I'm not trying to hurt anybody," Stafford said. "At the same time, you have to keep your head up if you're going to make a play over the blue line like that."
The Blackhawks' penalty killing sparkled, stopping all seven Buffalo chances. While holding a 3-1 lead late in the second period, the Blackhawks killed eight straight minutes of Buffalo power play and allowed one shot during the span.
"We did a terrific job on the PK," Huet said. "We blocked a lot of shots. I guess that was the turning point. We didn't let them back into the game."
"The way we shut them down, the momentum, the crowd, it turned to our advantage," Quenneville said. "It was good to see."
Ales Kotalik scored for Buffalo, which dropped its second straight.
Buffalo's Patrick Lalime, the backup to Ryan Miller, made 21 saves in his first start since Dec. 26.
Lalime, who played the past two seasons with the Blackhawks, was shaky as he faced his former teammates for the first time since signing with the Sabres as a free agent in July.
"Personally it seems that I can be better," Lalime said. "We didn't capitalize on our chances, but still we didn't give them much."
Added Buffalo coach Lindy Ruff: "The power play wasn't very good and obviously they got some momentum off that. We need to pick up that area of our game. We had some good opportunities and have got to put them away."
Kotalik opened the scoring midway through the first period following a failed Chicago clearing attempt. He ripped in a shot from the slot after being set up by Adam Mair.
Sharp tied it at 1 with 4:24 left in the first. Lalime stopped Ben Eager's shot from the slot, but Sharp's rebound attempt trickled in under Lalime's arm as he was sprawled on the ice.
Toews scored 2:29 later - also on a shot Lalime misplayed - to put Chicago ahead 2-1. Lalime appeared to have stopped Toews' shot from the left circle, but the puck rolled between his right arm and body, and landed in the net.
Havlat made it 3-1 at 5:53 of the second to complete a three-on-one break. Havlat carried the puck down the left wing, then beat Lalime with a shot high on the stick side.
The Blackhawks then killed eight straight minutes of a Buffalo power play.
The first two minutes were set up by a penalty for too many men on the ice. The final six were levied against Eager - a minor for cross-checking and a double-minor for roughing - after he retaliated against Stafford for the hit on Keith.
Chicago allowed one shot on goal, to Tim Connolly, during the Buffalo advantage. The Blackhawks nearly scored after Adam Burish knocked the puck away from Lalime, who had wandered out to play it.
Wisniewski made it 4-1 only 17 seconds into the third with his first goal of the season. He beat Lalime with a low shot from the blue line.
Notes: While with the Blackhawks the past two seasons, Lalime was 20-18-3 with a 2.88 GAA in 44 games. ... Buffalo RW Maxim Afinogenov missed his fourth game with a groin injury and RW Patrick Kaleta missed his 11th with a head/neck injury. Both are on injured reserve. ... The crowd of 21,684 was Chicago's 20th sellout in 20 home games this season.