Cory Conacher scored the tying goal late in regulation and Kyle Turris won it at 2:32 of overtime, as the Ottawa Senators claimed a 3-2 victory over the Montreal Canadiens in Game 4 of this Eastern Conference quarterfinal.
Turris was harassed by a Canadiens defender in the left circle, but the Sens forward escaped long enough to send a wrister to the Habs' net, which deflected off the elbow of defenseman Raphael Diaz and caromed past Peter Budaj -- who began the extra session in place of the injured Carey Price -- to end the contest.
Mika Zibanejad also tallied for the Senators, who took a commanding 3-1 series edge with Game 5 set to return to Montreal on Thursday.
"I thought both teams played hard and played hockey. They were better than us for awhile, we were better than them for awhile," offered Senators head coach Paul MacLean.
Craig Anderson stopped 26 shots for Ottawa, which can advance to the second round for the first time since 2007 with one more victory.
PK Subban and Alex Galchenyuk lit the lamp early in the second period for the Canadiens. Price ended up with 30 saves, but Budaj was saddled with the loss.
Following a scoreless first period, Subban put the Habs up 1-0 at 2:52 of the second, with a rising wrister from the bottom edge of the right circle off a rush.
Galchenyuk followed with a high shot from the left-wing side 62 seconds later. Jeff Halpern aided the tally, with his perfect lead pass to the rookie winger, who stepped into the dish in stride and fired high over Anderson to the far side.
Price was good on all 10 Ottawa shots in the middle 20 minutes, but couldn't hold on late.
The hosts finally cracked the scoreboard with 8:05 left in regulation, when Zibanejad's redirection of a Chris Neil pass from the right-wing boards skittered into the net.
Despite overhead replays which seemed to reveal the puck being directed in with a distinct kicking motion, the goal was allowed to stand.
"It was a kicking motion, there's nothing you can do about it, it's a league decision," said Habs head coach Michel Therrien.
Anderson was sent to the bench for an extra attacker with 1:25 to play, and the Sens sent the game into the fourth period when Conacher slid a loose puck between Price's pads with 22.6 seconds remaining.
Ottawa has never squandered a 3-1 series edge in modern playoff history ... Subban earned his first career Norris Trophy nod earlier on Tuesday when the NHL announced the three finalists for best defenseman ... The Canadiens once again played without captain Brian Gionta along with forwards Ryan White and Lars Eller, dressing forwards Halpern, Mac Pacioretty and Gabriel Dumont in their places ... Senators defenseman Eric Gryba returned from his 2-game suspension for his illegal hit on Eller ... The Canadiens rallied from a 3-1 series deficit in the 2010 Eastern quarterfinals against the Washington Capitals ... Conacher, Zibanejad and Galchenyuk all recorded their first career playoff scores.