Jhonas Enroth continues to make the case for more playing time.
With starter Ryan Miller struggling, coach Lindy Ruff gave Enroth his third start in four games. He's won all of them. Miller won the other one -- a 6-5 OT victory against Winnipeg on Tuesday.
Enroth has allowed just eight goals in his five wins.
"He's done a good job coming in," said center Derek Roy, who has four goals and eight points during the winning streak, including the first goal on Friday. "He's stepped up in the games, made big saves for us, and has gotten some big wins for us."
Though the Sabres were outshot 37-21, they made the most of their opportunities by crashing the net. All five goals were scored from within 10 feet of the net.
"I thought the difference in the game was they went to the net way harder than we did and with more determination," Ottawa coach Paul MacLean said. "I think it's a step back because of the score, but it's also something we can learn from."
The Sabres scored a pair of early goals 16 seconds apart, both on rebounds. Roy beat Craig Anderson just 2:09 into the game, and Matt Ellis scored at 2:25 on the Sabres' sixth shot of the night, sending Anderson to the bench in favor of Alex Auld.
"It was 2-0," MacLean said when asked why he pulled Anderson -- the third time this season he's done so.
The goaltending change helped briefly, as Sergei Gonchar beat Enroth for a power-play goal at 4:38, but Jordan Leopold restored Buffalo's two-goal lead at 14:40, snapping home a pass from Drew Stafford.
Rookie Luke Adam fired home a pass by Thomas Vanek four minutes into the third period and Ville Leino scored his first goal since opening night 57 seconds later as the Sabres (10-5-0) put the game away and sent the Senators (7-9-1) to their fifth loss in as many games this month.
Enroth is 12-0-1 since his last loss in regulation -- a 1-0 defeat last Nov. 24 at Pittsburgh.
"I have to stay humble," he said. "Hockey is a sport where it can turn around quick. I go out there and try to play every game like it would be my last game."
His best save came midway through the second period when he robbed Zack Smith's tap-in try on a 2-on-1 shorthanded break. Otherwise, he wasn't tested severely despite the large volume of shots.
"They had a lot of shots, but a lot of them came from pretty far out," Enroth said. "It was pretty easy. There weren't too many really good chances."
In contrast to the Sabres, most of Ottawa's shots came from the perimeter -- much to the displeasure of their captain.
"They are probably one of the best teams around the net in the League," said Daniel Alfredsson, who returned after missing five games with a head injury. "We were not as good as we need to be in front of their net and they made the most of their opportunities."
Ottawa continues its six-game road trip with a visit to Toronto on Saturday. The Sabres head for Boston and a meeting with the red-hot Bruins.
Material from team media was used in this report