Paajarvi put the Senators up 1-0 at 15:47 of the first period when he batted in the rebound of Cody Ceci's shot. The goal was Paajarvi's fourth of the season and first in 19 games.
"It was a big goal for us at a big time," Stone said. "It got us the lead and we were able to play with it for the rest of the night, and that makes it that much easier."
The Senators struck for two quick goals in the second period. Ryan Dzingel chipped the puck ahead to Ryan, who scored from the low slot for a 2-0 lead at 7:26. Stone made it 3-0 at 7:39 after Chris Tierney won a face-off to Stone for a shot inside the far post.
"You get two goals that quickly apart and get that three-goal lead, [opponents] start to take chances," Stone said. "We've played from behind and we understand how hard it is."
Foegele cut through the Ottawa defense and scored from along the goal line to cut the Senators lead to 3-1 at 11:24.
Ottawa restored its three-goal lead when Wolanin finished a pass across the top of the crease from Brady Tkachuk to make it 4-1 at 16:25.
Nilsson made 12 saves in the third period for his fourth win in his past five starts.
"From my perspective standing back there, we didn't give them a whole lot," Nilsson said. "We played very hard throughout the whole ice and didn't give them a lot of time and space."
Ottawa blocked 27 shots, seven by Ceci.
"Being better defensively makes us win games," Senators coach Guy Boucher said. "We look good. We don't just win them, we win them solid."
