DENVER — A collective goof in 3-on-3 overtime decided Saturday’s first clash between the Western Conference’s established division leaders.

Colorado’s Mikko Rantanen gave up the puck along the boards as Calgary’s Johnny Gaudreau drifted behind Nathan MacKinnon and Devon Toews. Gaudreau took a pass and went in alone. He beat Avalanche goaltender Pavel Francouz low 37 seconds into overtime for a 4-3 Flames win.

“We worked so hard, especially for the final 40 minutes. We checked hard, we played hard. We were on the attack,” Avalanche coach Jared Bednar said. “And then we just let a guy go in behind us in overtime and they put it away. To sort of forget about our checking game when it goes to 3-on-3, when it’s even more important, is disappointing.

“Lot of positives to take out of the game, but still clearly, lots to work on.”

Colorado starting goaltender Darcy Kuemper was pulled after allowing three goals on 15 shots. That failed to fire up the Avalanche immediately. Kurtis MacDermid then dropped the gloves with the Flames’ Milan Lucic. It was a long tilt with plenty of swinging and no clear victor.

Francouz, who entered the in relief, had a significant part in turning the tide. He came in cold but steadied the Avalanche, playing conservatively and stopping every shot through almost two periods.

“I don’t think it was me,” Francouz said. “I think we just picked up our game right away.

“It’s kind of (a) cliché, but what coach meant to do was fire us up, and that’s exactly what happened.”

Both times Kuemper has been pulled for performance reasons this season, the Avalanche have gone to overtime. Last time, Jan. 8 against Toronto, Colorado completed the comeback.

“At that point, we needed a little bit of something,” Bednar said. “Tough call to make. Darcy’s start, and those certainly weren’t on him. But for me, I just felt like we’ve seen him sharper.”

While MacDermid and Lucic watched from the penalty boxes, Cale Makar bailed out the Avalanche after a turnover, dipping and sliding to break up a Calgary 2-on-1. He then burst out of the mess with the puck. Colorado took it end-to-end and MacKinnon tied the game at 3.

It was easy come, easy go for the Avalanche’s first two leads of the game. Colorado came at Calgary goaltender Daniel Vladar (33 saves) in waves on the first shift of the first period. Gabriel Landeskog went around the net, spotted the puck when he resurfaced and buried a shot 42 seconds in.

Less than two minutes later, it was determined Kuemper fired the puck directly over the glass. Five seconds into his delay-of-game penalty, served by Nicolas Aube-Kubel, the Flames’ Elias Lindholm tied the game at 1.

Andre Burakovsky’s power-play goal gave the Avalanche a 2-1 lead that lasted just 1:06. Lindholm scored again with an assist to former Colorado fan favorite Nikita Zadorov. It was Zadorov’s first game back in Denver following the trade that brought Brandon Saad to the Avalanche in 2020.

Valeri Nichushkin returned to the lineup after missing two games with an upper-body injury. He assisted on each of the Avalanche’s first two goals.

Colorado’s Tyson Jost was hit by a puck in the third period and headed down the tunnel holding a towel to his head. He didn’t return.

With a helper on MacKinnon’s goal, Makar pushed his assist streak to 11 games, one short of Joe Sakic’s franchise record set in 1991-92.

“Especially once Nate tied it up there, I thought we took over and played really well,” Landeskog said.

The Avalanche and Flames will have another crack at each other soon. They meet again at Ball Arena after the Avalanche’s upcoming three-game road trip.

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