Fehervary gave the Capitals a 1-0 lead at 2:46 of the first period with a slap shot from above the left circle that beat Luukkonen five-hole.
Zemgus Girgensons tied it 1-1 at 15:42 when he redirected Dahlin’s shot glove side on Lindgren.
Peterka put Buffalo ahead 2-1 at 16:50 on a power play. Zach Benson’s short centering pass hit Tuch’s stick and deflected to Peterka, who scored into an open net past a sprawling Lindgren from along the goal line.
Peterka then made it 3-1 at 10:54 of the second period. He scored all alone in front after Tuch forced a turnover by Nicolas Aube-Kubel above the right circle.
“That guy’s stick is insane,” Peterka said of Tuch. “It’s like when you have the car and it goes back and forth. He’s winning so many pucks on the forecheck, which makes it so easy to play with him. I was pretty glad that came to me.”
Strome cut it to 3-2 at 19:14, burying a rebound in the crease with his backhand for a power-play goal.
“Overall, we didn't play really good, so we were lucky we were in that kind of spot in the third period,” Fehervary said. “But then it just turned on us. I mean, we just need to be better overall, like more sharper in the [defensive] zone, and we just need to have more checking.”
Dahlin pushed it to 4-2 at 3:03 of the third period with a one-timer from the left point on a power play.
The Sabres finished 2-for-2 on the power play after going 0-for-18 with the man-advantage in their previous seven games.
“We’ve had a lot of talks and it finally trickled in,” Dahlin said. “We’ve been having a lot of chances the last, whatever, five games on the power play, but we haven’t scored. That can create frustration, but we just stayed with it and scored two really good goals today, and we just got to continue to build.”