MONTREAL -- Cory Conacher scored twice, Eric Condra had a goal and two assists, and the Ottawa Senators beat the Montreal Canadiens 6-1 on Thursday night for their first playoff series win in six years.
Craig Anderson made 33 saves and Kyle Turris scored for a third straight game. Zack Smith and Daniel Alfredsson added goals for Ottawa, the seventh seed in the Eastern Conference.
The Senators upset Northeast Divison champion and second-seeded Montreal with a 4-1 series victory, winning three straight games after splitting the first two at the Bell Centre.
Ottawa had lost four straight playoff series, including the 2007 Stanley Cup Finals to Anaheim since winning that year's Eastern Conference final against Buffalo.
P.K. Subban scored late in the first period for the Canadiens, who were without No. 1 goalie Carey Price.
Peter Budaj stopped 23 shots in his first career playoff start in place of Price, who was injured on the final play of regulation on Tuesday night.
In addition to Price, the Canadiens were also without captain Brian Gionta and forwards Brandon Prust and Ryan White, who are also injured.
Turris, who scored the overtime winner against Budaj on Tuesday in Ottawa, restored Ottawa's two-goal lead at 3-1 midway through the second when he got credit for a short-handed effort.
Alfredsson scored his 49th career playoff goal on a power play 6:22 into the third to make it 4-1. Conacher, who put put the Senators up 2-0 in the first, scored his second goal of the game on another man advantage at 12:27 to increase the lead to four.
Both teams were called for too-many-men minor penalties midway through the second and the Canadiens were on the power play, trailing 2-1, when disaster struck for the home side.
Montreal center Tomas Plekanec pushed Turris toward the goal and the Ottawa center collided with Budaj as he fell to the ice.
Eric Condra's shot banked into the net off Turris and a video review upheld the goal ruling on the ice.
Budaj, who was beaten 2:32 into overtime on Tuesday night, coughed up a fat rebound on Matt Kassian's shot from the left side that led to the opening goal.
Smith jumped on the puck and skated past Budaj to tuck a backhand around his left pad into the right side of the net.
Conacher, who beat Price for the tying goal with 22.6 seconds left two nights earlier, made it 2-0 when he put a loose puck in the goal mouth into a wide-open left side after Condra's shot hit the right post.
Subban sent Montreal into their dressing room within one at 2-1 when his shot from the left point beat Anderson for a power-play goal with 14.9 seconds left in the first.
Canadiens left winger Rene Bourque put a shot off the right post in the first and right winger Colby Armstrong hit the crossbar in the second after Plekanec's pass sent him in on a breakaway with Montreal still within one.
NOTES: Left winger Guillaume Latendresse was left out of the Senators' lineup for a third straight game. ... Ottawa defenseman Patrick Wiercioch remains sidelined by a lower-body injury that forced him to leave early in Game 3, won 6-1 by the Senators in the first game in Ottawa. ... Budaj had previously appeared in five playoff games, all in relief, including Tuesday night's 3-2 overtime loss in Game 4 in Ottawa. Prior to that, Budaj's last playoff game was April 22, 2010, when he allowed one goal on four shots after taking over for Craig Anderson in Colorado's 5-0 loss in San Jose. Budaj came off the bench to replace Jose Theodore three times in the Avalanche's second-round loss to Detroit in 2008 when they were swept by the Red Wings. ... Robert Mayer dressed as Budaj's backup. Mayer, who has yet to make his NHL debut, went 16-17-3 with a 2.93 goals-against-average and .908 save percentage in 38 games with AHL Hamilton this season.