Erik Karlsson and Chris Phillips also found the net in the initial frame while Chris Neil added what turned out to be the game-winner in the second period for the Senators, who improved to 6-3-1 on the season.
Craig Anderson earned the win with 20 saves for Ottawa.
Jhonas Enroth was touched for all four goals on 24 shots for Buffalo.
Ray Liotta sues skin care company over use of likeness
Millions of Getty images now available for free via embed tool