TORONTO (AP) The Montreal Canadiens weren't even supposed to be here.
All but eliminated from playoff contention, they'd shipped out key veterans at the trade deadline and were already focused on next season when COVID-19 forced the NHL to pause in mid-March.
The league's 24-team restart gave Montreal a second life, and a roster not given much of a chance in this tournament is now one win from adding an incredible chapter to an unbelievable year.
Jeff Petry scored 5:33 into the third period as the Canadiens rallied from two goals down and beat Pittsburgh 4-3 in Game 3 on Wednesday night, pushing the Penguins to the brink of elimination in the best-of-five series.
''We've just done it by working hard,'' said Montreal coach Claude Julien, who shook up his lines in the second period with his team down 3-1. ''At the end of the day, we know where the experience is. The only way we can counter that is with our work ethic and our commitment and desire.
''We lack experience compared to the other team, but we're trying to make it up with our compete level.''
Shea Weber had a goal and two assists for Montreal, Paul Byron added a goal and an assist, and Jonathan Drouin also scored. Ben Chariot also had had assists.
Carey Price stopped 30 shots for the Canadiens - the 12th seed in the Eastern Conference as part of the NHL's 24-team restart to its pandemic-delayed season. Montreal can advance to the normal first round with 16 teams with win in Game 4 on Friday.
Patric Hornqvist, Jason Zucker and Teddy Blueger scored for fifth-seeded Pittsburgh, which led 3-1 after Blueger's goal 5:34 into the second. Matt Murray finished with 27 saves.
''We just made a few mistakes,'' Penguins captain Sidney Crosby said. ''This time of year, those mistakes are magnified. They're opportunistic. They're waiting for those mistakes and they capitalized on them.
''We might have been guilty of getting a little too loose there with the lead, and that changed pretty quick.''
Canadiens forward Brendan Gallagher suited up after briefly leaving the Penguins' 3-1 victory in Game 2, but was clearly laboring at times with an undisclosed lower-body injury.
''As long as you can help the team, you're going to be out there,'' Gallagher said. ''I would never put myself in a situation where I'm gonna hurt the team.''
Drouin pulled the Canadiens to 3-2 at 10:13 of the middle period when he redirected Chiarot's point shot past Murray.
Byron tied it with 4:10 left in the period, just seconds after a penalty on Pittsburgh's Evgeni Malkin expired. Byron deftly moved Nick Suzuki's rebound from his skate to his stick and sneaked a second-effort wraparound just over the goal line.
Joel Armia nearly gave Montreal the lead early in the third but his one-timer pinballed around the crease during a power play. However the Canadiens kept up the pressure, and Petry, who provided the overtime winner in Game 1, roofed a shot past Murray's ear from a sharp angle for their second lead of the game.
''There's no bad shot and at this time of the year,'' Petry said. ''I was able to pick my spot.''
The Penguins, who had the seventh-best record in the NHL when the season was suspended in mid-March, pushed as the period wore on, with Price denying Kris Letang down low.
Pittsburgh went on the power play with 3:32 left in regulation, but Price handled Sidney Crosby's one-timer comfortably without giving up a rebound on the only shot against.
The Penguins pulled Murray and continued to press, but weren't able to get the equalizer.
Montreal jumped on the scoreboard first in front 4:57 into the game as Weber fired his third shot of a chaotic sequence by a down-and-out Murray.
With the Canadiens already down a man, Weber buried Hornqvist in the corner and was going to be assessed a penalty. Montreal's captain seemed to be waiting for Malkin to give the puck away for a 5-on-3, but he instead whipped a cross-ice pass to Hornqvist, who made no mistake at 8:40.
Pittsburgh stayed on the power play with Weber now in the box, and Zucker made it 2-1 just 59 seconds later when Bryan Rust delivered a sneaky feed in the slot for the winger to rip a shot upstairs.
''You're playing a team that knows exactly what to do to get back into a series,'' Julien said of the Penguins, who won the Stanley Cup in both 2016 and 2017. ''We're aware of that, so we need to be playing our best game come Game 4. We've got to be ready.
''We can't get overconfident, but we've got to have the confidence to be able to close it off.''
NOTES: Pittsburgh C Jared McCann sat out in favor of Sam Lafferty. ... The Canadiens made one lineup change with Jake Evans swapping in for Jordan Weal on the fourth line. Evans was drilled into the boards by Tanev in the second period and did not return. ... The Canadiens finished 0 for 5 on the power play to fall to 0 for 10 in the series. ... The Penguins went 2 for 3 on the man-advantage to improve to 3 for 15.