CALGARY, Alberta (AP) - Matthew Tkachuk scored twice and Mike Smith made 26 saves for his first playoff shutout in nearly seven years, and the Calgary Flames blanked the Colorado Avalanche 4-0 on Thursday night in Game 1 of their first-round Western Conference playoff series.

Rookie Andrew Mangiapane and Mikael Backlund also scored as Calgary won its first playoff game since beating Anaheim 4-3 in overtime on May 5, 2015.

The shutout was Smith's first in the postseason since May 20, 2012, when he made 36 stops while with the Phoenix Coyotes to shut out the Los Angeles Kings in Game 4 of the Western Conference final. The Coyotes lost the next game and Smith hadn't played a playoff game since.

A key sequence came early in the second as the Avalanche went to the power play for the third consecutive time. With all the momentum with Colorado, Smith made two key glove stops 30 seconds apart to keep the game scoreless.

First, he made a backhand snag off the stick of Gabriel Landeskog, who was left alone in front. Then, with a little extra flourish afterward, Smith threw out his glove to snag Derrick Brassard's dangerous snap shot. From that point through the end of the game, chants of "Smitty! Smitty! Smitty!" broke out regularly from the raucous, sold-out, red jersey-clad crowd.

It took until 14:25 of the second period for the game's first goal - but Mangiapane's unassisted score was a highlight-reel effort. The sequence began with Garnet Hathaway's heavy hit on Erik Johnson on the side boards. Mangiapane collected the loose puck and took it to the net where he weaved around Nikita Zadorov and carried the puck across the top of the crease before sending a backhander from his knees past a sprawling Philipp Grubauer.

Hathaway also had an indirect hand in the Flames' second goal later in the second as he was hauled down while sending a shot off the crossbar to draw a penalty. Calgary converted on the power play at 18:58 to take a 2-0 lead to the second intermission. On the goal, Mark Giordano's point shot was deflected out of the air by Tkachuk. Called a goal on the ice, Avalanche coach Jared Bednar challenged it, suggesting it was deflected by a high stick, but the goal stood after a lengthy review.

Backlund made it 2 for 4 for Calgary with the extra man when his goal at 17:01 of the third made it 3-0.

Tkachuk sealed it 14 seconds later with an empty-netter off an assist from Smith.

NOTES: Grubauer made 28 stops for Colorado. ... The Flames finished the regular season on a 1-for-38 skid on the man advantage over the final 13 games. ... Calgary opened up the playoffs at home for the first time since 2006. ... It was the first playoff game as a head coach for Bill Peters, who failed to make the postseason in his four seasons with Carolina.

UP NEXT

Game 2 is Saturday night in Calgary.

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