It was Price's third shutout of the season and No. 47 of his career. Petry recorded his first career four-point game.
Playing their first game since Jan. 21, the Panthers (28-17-5) were shut out for the first time this season. They had won six in a row, scoring at least four goals in each of the victories.
Price beat Sergei Bobrovsky in a battle of the NHL's two highest-paid goaltenders. Bobrovsky stopped 31 shots.
Montreal jumped in front 5:25 into the first period. Suzuki finished off a 2-on-1 for his 10th of the season.
The Panthers struggled to clear bodies out of their crease for most of the game and it cost them in the second.
On missed coverage by Florida, Lehkonen made it 2-0 by redirecting Petry's shot between Bobrovsky's pads at 6:01 for his 12th of the season.
Tatar added to Montreal's lead at 13:35 on a pass from Phillip Danault behind the net. Four Panthers players surrounded Tatar in the crease, but the winger still managed to get his stick on the puck, earning his team-leading 19th goal.
Price did his part to shut down the league's top-ranked offense. He made his best stop on Jonathan Huberdeau on a breakaway in the first.
Claude Julien coached his 400th regular-season game with the Canadiens. ... Montreal sent Jesperi Kotkaniemi down to the AHL's Laval Rocket.
Panthers: Visit the Toronto Maple Leafs on Monday night.
Canadiens: Host the Columbus Blue Jackets on Sunday.
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