For two periods Saturday night, Brian Elliott sat at the end of the Ottawa Senators bench.

The third period was a whole different story.

The Senators backup replaced injured starter Pascal Leclaire to start the third and made 16 saves to pick up the win as Ottawa topped the Buffalo Sabres 5-3.

"I don't know how fast my heart was going when I got in there," said Elliott. "The guys played really well in front of me. I felt I played pretty good and obviously they spotted me that lead and that helped as well."

Daniel Alfredsson led the way with two goals and an assist for Ottawa and Filip Kuba scored his first of the season as part of a four-point night as the Senators (11-6-3) extended their winning streak to three games.

Chris Kelly and Milan Michalek, with the game-winner, also scored for the Senators in front of 17,206 at Scotiabank Place.

Thomas Vanek, Patrick Kaleta and Jason Pominville scored for the Sabres (12-6-2). Former Senators goalie Patrick Lalime faced 26 shots in just his third start of the season.

A team whose offence was questioned early in the season, the Senators have scored 14 goals in their last three games.

"I think it's confidence and a little bit of luck," said Alfredsson. "We're playing with more confidence and you can feel it in the locker-room. When you score five like tonight you've got to be happy."

Elliott was called into action after Leclaire left the game with a lower-body injury. The Sabres' Jochen Hecht collided with the Senators netminder in the second and Leclaire seemed to favour his left leg. He finished with 24 saves.

Senators head coach Cory Clouston said Leclaire would be re-evaluated on Sunday.

After a sluggish start to the game, Buffalo got on the board with less than a minute to go in the first on the power play. Parked at the side of the net, Vanek picked up a rebound and beat Leclaire shortside.

The Senators responded with a power-play goal of their own in the opening minute of the second period as Kuba fired a shot from the blue-line.

"I thought we came out real solid in the second period," said Clouston. "The first 12 to 13 minutes we played really well. We did a lot of good things defensively and that created offensive opportunities."

Ottawa took the lead at 8:14 of the second when Alfredsson scored his seventh of the season on a quick wrist shot.

The Sabres took four minor penalties in the period and were down two men for 66 seconds but the he Senators couldn't capitalize. Ottawa finished the game 1-for-5 with the man advantage.

"I think we took a couple penalties that we didn't need to take," said Buffalo head coach Lindy Ruff. "That gave them a little bit of momentum and they carried it from there."

Ottawa made it 3-1 early in the third when Kelly tipped Matt Carkner's point shot. Michalek then made it 4-1 with his tenth of the season on an odd-man rush.

"I don't think we even need to focus on goaltending," Ruff said. "I think the focus has to fall on our 5-on-5 play. That 4-on-3 that they scored against was just a fact that two of our forwards didn't get back."

After Alfredsson made it 5-1, Kaleta and Pominville scored less than two minutes apart to pull Buffalo to within two with just over nine minutes remaining.

Chris Neil was assessed a double-minor with 4:11 remaining in regulation, but the Sabres was unable to capitalize.

Buffalo went 1-for-7 on the power play.

"We came out strong at the start of the period and then we took the penalty at the end," said Ottawa's Mike Fisher. "But we stayed composed and we stuck with it and it was good for us."