Kadri put Calgary ahead 4-3 at 10:04, scoring high to the stick side off a pass from Milan Lucic, before Lucic made it 5-3 at 16:43 with a shot that deflected off Reimer's pad.
Toffoli extended the lead to 6-3 with an empty-net goal at 18:22, and Kadri scored five-hole at 18:42 for the 7-3 final.
"We weren't ready to play and it trickled into our game later on, too," Sharks defenseman Mario Ferraro said. "It's hard to chase the game. If those [first] two goals didn't happen, maybe our mindset is a little different."
NOTES: The Flames tied the fifth fastest two goals to begin a game in NHL history and broke their record set by Doug Risebrough (:09) and Colin Patterson (:32) on March 11, 1987, in a 6-1 win at the Hartford Whalers. … Toffoli, Dube and Lindholm tied for the fourth fastest two points from the start of an NHL game. … Lindholm set a franchise record Sunday when he scored twice in the first 35 seconds of the third period, the fastest two goals by one player to start a period. … Karlsson had an assist to extend his point streak to eight games (one goal, nine assists). He has 30 assists in 34 games to tie Brent Burns (2018-19) for the fewest games to reach 30 by a defenseman in Sharks history. … Ferraro had two shots and two hits in 19:07 after missing 10 games with a foot injury. … Sharks forward Matt Nieto had an assist in his 600th NHL game. … Benning played his 400th NHL game. … San Jose forward Tomas Hertl did not play. He was serving the first of a two-game suspension for high-sticking Lindholm on Sunday.