Joel Farabee had a goal and an assist for the Flames (5-6-0), who went 4-0-0 on their four-game homestand. Matt Coronato and Simon Nemec each had two assists, and Devin Cooley made 26 saves to win his fourth consecutive start.
Mikael Backlund scored in his return for Calgary after missing the past two games with an upper-body injury.
William Nylander and Easton Cowan scored for the Maple Leafs (7-5-2), who had won four straight. Sergei Bobrovsky, who was making his 800th NHL start, made 30 saves.
Auston Matthews recorded his 800th career point (437 goals, 363 assists) with an assist for Toronto, becoming the fastest in franchise history to reach the mark (703 games).
Maple Leafs forward Kirill Marchenko left with a lower-body injury in the second period and did not return. He took a hit from Yegor Sharangovich and fell awkwardly to the ice before playing one more 14-second shift and leaving the game.
Gridin gave the Flames a 1-0 lead at 10:05 of the first period, snapping a shot from just below the left face-off dot into the top corner over Bobrovsky’s blocker.
Backlund extended it to 2-0 at 11:50 when he took a cross-ice pass from Matt Coronato and scored from the left circle on a shot that also beat Bobrovsky over his blocker. It was Backlund’s 609th career point to tie Johnny Gaudreau for fifth place on the Flames’ all-time list.
Gridin’s second goal made it 3-0 just 25 seconds into the second period, snapping a shot from the left circle to the far side past Bobrovsky’s glove.
Cowan cut it to 3-1 at 12:54, redirecting a slap pass from Troy Stecher past Cooley.
Nylander made it 3-2 at 6:06 of the third period when he took a cross-crease pass from Jack Roslovic and lifted a shot past a diving Cooley.
Farabee and Martin Pospisil then scored empty-net goals at 18:35 and 19:21, respectively, for the 5-2 final.
