Tied at one entering the third period, Connor McDavid gave the Oilers a 2-1 lead with a powerplay goal at 7:28. McDavid took a pass from Leon Draisaitl and walked into the high slot, ripping a shot off the post and in to extend his personal point-scoring spree to 16 games (15G, 17A).
It was a tough call on Andrew Mangiapane, who was whistled for holding after wrapping his arms around Darnell Nurse in the offensive zone.
That's the way it finished, and as such, the Battle of Alberta season series goes the way of the Oilers, two games to one.
The Flames pressed - hard - for the equalizer and out-shot the Oilers 24-4 in the third period for a dominant 47-22 advantage overall. Five-on-five, the homeside had their most productive night of the season, putting up 80 shot attempts to Edmonton's 26.
Credit to Oilers goalie Stuart Skinner, who was the difference with a career-high 46 stops.
Mikael Backlund scored the Flames' lone goal and put a shot off the post with only four seconds left in regulation that would have sent the game to overtime.
Jacob Markstrom made 20 saves.
With the loss, Calgary's record drops to 16-13-7 on the year.
The Flames got off to a great start and registered six of the first eight shots of the game, in spite of the sloppy flow you'd expect after three days away from the rink. However, a too-many-men penalty put the vaunted Oilers powerplay on the attack at 12:47, and many of the 19,289 on hand waited nervously as McDavid and Edmonton's top-ranked unit took to the ice.
But it was Calgary that had the better of the chances, including a splendid, solo effort from Mangiapane at the end of a shift, dangling Draisaitl and Zach Hyman before sliding a soft shot that just skittered wide of the open side.
The Oilers came into the night 18-for-43 (43%) in their last 12 outings, so for the Flames to make a statement early on that side of the puck was a good sign for the locals. Unfortunately for the Flames, the PK couldn't hold the Oilers' top snipers off the board all night.
From there, the pace picked up. The Flames held the Oilers in their own end for an extended period, but the visitors turned it back in transition and nearly sniped the opening tally.
McDavid was fresh out of gas after a 1:43-long stay, but had enough in the tank to carry the puck up the left side and spot a cruising Jesse Puljujarvi, who took the feed from No. 97 between the hashmarks and leaned into a snapper that Markstrom emphatically gloved down.
Not to be outdone, Oilers goalie Stuart Skinner made a fancy pad stop off Rasmus Andersson, who spun and fired from point-blank range.
Shots on goal favoured the Flames 10-9 in a highly entertaining first period.
Ultimately, persistence paid off and the Flames grabbed a 1-0 lead at 1:12 after pinning the Oilers in their own end for the entire time off the opening faceoff.
Eventually, the puck popped loose at the right dot and Blake Coleman chopped a backhand into a mess of traffic in front. Skinner made the initial stop with the right pad, but the rebound caromed out to a waiting Backlund, who heaved it over the blocker for his seventh of the year.
Andrew Mangiapane picked up the other assist; and while the blueliners, Andersson and Noah Hanifin did not register a point on the play, they were equally influential, keeping the play alive on numerous occasions and making smart decisions with the puck.
The Oilers, though, quickly replied and made it a 1-1 game at 4:58 when Tyson Barrie blasted a slapper from long distance through a maze, beating Markstrom clean under the glove.
Edmonton went back to the powerplay at 6:46 when Mangiapane took a seat for slashing and Markstrom - again - pulled off the incredible.
The impossible.
The patented Draisaitl one-timer was twice turned aside - first, when McDavid feathered a pass through a seam, allowing No. 29 to get full wood on his backdoor blast. The second, a longer, but equally impressive diagonal feed from Ryan Nugent-Hopkins that connected with the German a tad lower below the circle.
But both times, Markstrom got across and kicked out the pad, snuffing the chances in a fine show of athleticism.
The Flames got their first crack on the powerplay when Dillon Dube was hauled down in the slot at 13:10. Tyler Toffoli had the best chance for the homeside, walking into a slapper at the left circle and blistering it off the bar.
Not-so-fun fact: Toffoli came into the night having struck iron seven times (four posts, three crossbars) this year. Make it eight. That leads all Flames skaters.
The Flames extended to a 23-18 advantage on the shot clock after out-gunning the visitors 13-9 in the middle stanza.
Markstrom kept it a 1-1 game early in the second when he stoned Hyman off the rush, after the winger trailed and took a drop pass from McDavid, waltzed in and fired.
