Matt Puempel and Kyle Turris scored second-period goals, and backup Andrew Hammond made 34 saves as the Senators beat the New York Islanders 2-1 on Friday night.
Ottawa improved to 9-1-1 in its last 11 games to remain within striking distance of Boston for the second wild-card spot in the Eastern Conference. The Senators trail the Bruins by five points with both teams having 15 games remaining.
"We need to keep stringing wins together to give ourselves a chance," said Hammond, who improved to 9-0-1. "The biggest thing for us is we stuck to our system, and I think we frustrated them a little bit."
The Islanders lost their third straight at home, including Tuesday's 2-1 defeat to the New York Rangers, and a 5-3 setback against Carolina on Feb. 28. They are 23-11 at Nassau Coliseum this season. New York will host Montreal on Saturday to complete a back-to-back.
"It's a couple of tight games, these last two," Islanders captain John Tavares said. "We have to find a way to get more opportunities. We have to play through it. We're not far off."
Tyler Kennedy cut the Islanders' deficit to 2-1 with 8:01 to go. Jaroslav Halak stopped 26 shots.
After a nondescript first period in which the Senators had a 9-6 shots advantage, Puempel scored his second goal of the season with a slap shot from the right circle at 6:32. Mika Zibanejad and Patrick Wiercioch assisted.
Turris made it 2-0 with 1:07 left in the second when he deflected in Erik Karlsson's shot for his 17th goal.
The Senators also beat the Canadiens 5-2 in Montreal on Thursday night.
"It was just a great road game," Turris said. "They were pushing pucks. We were collapsing in front of Hammond and forechecking pretty good. For a back-to-back, we did everything you could ask for."
Kennedy tipped in a drive by Lubomir Visnovsky for his sixth goal of the season and second with the Islanders since he was acquired from San Jose on March 2.
But Hammond then stopped Travis Hamonic and Anders Lee in close in the waning minutes. He has been stellar for the Senators in place of the injured Robin Lehner after playing most of the past two seasons with Binghamton of the AHL.
"It's all about playing a system and a way that gives us the best chance, and that's what we did against a great team," Senators coach Dave Cameron said. "You can't win in this league without goaltending. Hammy was real good."
Hammond made 22 saves in the second period, including a mask stop on Islanders defenceman Johnny Boychuk, which led to a brief delay while repairs were made to his headgear.
The Islanders couldn't solve Hammond on three power plays in the second, even getting several derisive cheers from the home crowd.
An undrafted free agent who signed with Ottawa in March 2013, Hammond has allowed two or fewer goals in each of his 10 starts for the Senators (32-24-11) this season.
The Islanders (43-23-4) won both previous meetings with the Senators in December. They trail the Rangers by one point in the Metropolitan Division but the Rangers have four games in hand.
"We have to stay the course and grind it out," Islanders coach Jack Capuano said. "Our structure has to be there and we have to execute and play with pace. But if you can't score, you can't win."
Kyle Okposo played his second straight game for the Islanders after missing 22 games because of a detached retina in his left eye. He had three shots on goal in 21:20 of ice time.
The Senators are 21-13-6 since Cameron took over for Paul McLean as coach on Dec. 8.
NOTES: The Islanders have outshot 35 of their last 41 opponents. ... Forward Michael Grabner was in the Islanders lineup in place of Frans Nielsen after being a healthy scratch against the Rangers. ... The Islanders were without injured D Nick Leddy for the second straight game. ... Ottawa scratched forward Colin Greening and defenceman Eric Gryba.