Coming off a 4-2 defeat to the same Habs just 48 hours earlier, they were eager to get back in the win column and add some points in the dogfight that is the all-Canadian North Division standings.
Thanks to an absolutely stellar goaltending performance from Jacob Markstrom, they did just that.
The big 'tender made 37 saves - including 15 in the second period when the Canadiens came in waves - as the Flames collected a 2-0 victory and improved to 3-3-1.
It was a nice early birthday present, as Markstrom will turn 31 tomorrow.
It was Montreal's first regulation loss of the season, as they fell to 5-1-2.
It was also Calgary's first win against the Canadiens in their last seven tries.
When he was signed in the summer as one of the biggest free-agent targets on the market, the hope was that Markstrom could be a difference maker for the Flames.
So far early in this season, he has done just that.
He's started all of Calgary's games except the Thursday tilt and parked back in his office, he put on a goaltending clinic.
Dillon Dube also returned to the fold after missing three games due to injury and was noticable all night, laying a massive hit on Jesperi Kotkaniemi behind the Montreal net in the middle stanza.
He also had a breakaway late in the third with Calgary clinging to a one-goal lead but was denied.
The Flames liked their finish in Thursday's outing, both of their goals coming late in the third period.
They promised to build on that Saturday, play with more passion and avoid getting behind early - something which has plagued them of late.
They got a golden chance to strike first when former Flame Brett Kulak was whistled for interference as he held up Sam Bennett near the Montreal blueline.
The Flames powerplay had scored nine times this season on 28 attempts, collecting at least one extra-man marker in each of their six games.
They increased that streak to seven when Johnny Gaudreau - who led the team in scoring with eight points coming into the game - caught a long high pass from Elias Lindholm with his glove, set the puck on the ice and snapped a wrister short-side over the shoulder of Jake Allen, who got the start after backing up Carey Price Thursday.
Tkachuk got the other helper.
Gaudreau has now picked up at least a point in every game he's played this year, the only Flames player to do so.