CALGARY — The Calgary Flames staged a massive third-period comeback on Thursday, led by captain Mark Giordano.

Down 4-1 after 40 minutes, Giordano produced the go-ahead goal and added two assists as the Flames scored five times in the third period for a thrilling 6-5 victory over the Colorado Avalanche.

Giordano broke a 4-4 tie at 13:47 when he jumped up into the rush, took a pass from Mikael Backlund, and snapped a shot over the blocker of Semyon Varlamov.

"If you're coming in late and their forwards are scrambling back, sometimes things open up," said Giordano, who has 14 points (2 goals, 12 assists) on the season. "I was happy (Backlund) found me there, it was a good spot to shoot from."

The goal came less than three minutes after the Saddledome had erupted with James Neal's tying goal.

"It felt good, obviously, for me," said Neal, who had been off to a slow start with just two goals in his first 13 games. "Personally, I want to score goals, You want to help the team win. It's been a little bit of tough sledding here at the start, but I've been through it before. You just try to stick with it and you get rewarded like I did tonight."

The sequence leading up to Neal's goal began when rookie defenceman Juuso Valimaki caught Matt Calvert with a bodycheck at the blue line, turning the puck over.

"He timed it perfect and to be able to keep the puck in the zone, all in one shot. That was a real turning point, too," Giordano said. "Really put them back on their heels and then we kept going."

Calgary began its comeback 47 seconds into the third on Elias Lindholm's power-play goal, his team-leading ninth goal of the season.

The man advantage was the result of a charging major on Ian Cole late in the second period after his heavy hit crumpled Mark Jankowski as he was looking back for a pass. Shaken up, Jankowski went to the dressing room. Deemed healthy post-game, he returned to sit on the bench in the third period, but did not play.

It was the response to the hit from Sam Bennett, who immediately fought Cole, that the players pointed to as the game's turning point.

"He's a feisty little kid. He definitely knows how to throw them," said Backlund. "That gave the team some momentum and some energy. Great job by him stepping up for the team and for Janko. It brought a lot of energy into the room going into the third."

Backlund, Sean Monahan and Michael Frolik also scored for the Flames (8-5-1), who have won three straight. Matthew Tkachuk added three assists. It's already the fourth time this season the Flames have come back to win a game in which they trailed after two periods.

Colin Wilson, Vladislav Kamenev, Sheldon Dries, Carl Soderberg and Gabriel Landeskog scored for Colorado (7-4-2), which has lost three of their last four. It was the first career goals for Kamenev and Dries.

"Five goals in the third is a lot. Give credit to them, but we definitely had a hand in letting them come back," said Colorado centre Nathan MacKinnon, who was held off the scoresheet and ended up a minus-3.

Just over a minute after Giordano's go-ahead goal, Frolik made it a two-goal lead, one-timing a Tkachuk feed for his sixth goal.

It would end up the eventual game-winner because the Avs got a power-play goal from Landeskog at 18:57 to set up a harrowing finish.

Mike Smith earned the victory, despite giving up five goals on 26 shots. He improved to 5-4-1.

Varlamov, who entered the game with a 1.62 goals-against average and a .950 save percentage, had 31 saves. He fell to 4-3-2. The five goals he surrendered in the third period came on 11 shots.

"Lack of detail and lack of commitment," said Avalanche coach Jerad Bednar. "We resorted back to bad habits like circling away from the puck and didn't pay attention to the detail."

Notes: Monahan extended his point streak to five games (2-6-8)... Rantanen's 21 points ties him with Joe Sakic (1996-97) for most points in an October.