The bigger problem is in goal. Devin Cooley had been one of the best early stories in the league. He'd won 4 straight and was the NHL's reigning 2nd star of the week before Colton Dach crashed into him with 12 seconds left in the 1st period in Edmonton. Cooley's leg hit the post, and he left with a lower-body injury and didn't return. Dustin Wolf finished the game, and Tristan Jarry stopped all 23 Calgary shots in a 4-0 Oilers win. Cooley is listed day-to-day. Between the Seattle game and this one, Calgary has 2 starts to cover in about 24 hours.
Colorado has an injury of its own on the blue line. Josh Manson left the New Jersey game near the Avalanche bench with a lower-body injury, favoring his left leg, and is day-to-day. If he can't go against the Flames, the expectation is that Noah Juulsen comes into the lineup. That's a real drop on the right side for a defense that just gave up 6 in Nashville a few games back.
Calgary's case is the 4-game run before Edmonton. The Flames beat Carolina, Minnesota, Detroit and Toronto, all at home, and allowed 6 goals across the 4 games. That's a tight, goalie-driven way to win, and it depends on whoever is in net. Calgary is also still without Jonathan Huberdeau, who has skated with the team but isn't close to returning, and Samuel Honzek, while Brennan Othmann is day-to-day.
Colorado hasn't been dominant either. The Avalanche went 2-3 in their last 5, with road losses in Philadelphia, New Jersey and Nashville, and won both home games in that stretch by 3 goals each. Denver has been where this team looks like itself. Calgary's 4-game streak came entirely at home, so the Flames now have to show they can win that way on the road, on short rest, with their goaltending still unsettled.