Nathan MacKinnon scored the overtime winner as the visiting Colorado Avalanche claimed a 3-2 victory over the Calgary Flames on Saturday night to even their opening-round Stanley Cup playoff series at one win apiece.

Game 3 of the best-of-seven series will be Monday in Denver.

Right after Calgary's Michael Frolik was stymied on a glorious opportunity, MacKinnon took a pass from Mikko Rantanen, sped down his off-wing and wired a glove-side wrist shot for the winner at 8:27 of the extra frame.

Avalanche goalie Philipp Grubauer made 35 saves.

Colorado responded to the 4-0 Calgary win in the opener with more intensity. That effort was rewarded when Matt Nieto opened the scoring with a short-handed goal 7:16 into the second period. Calgary was generating pressure on the power play, but T.J. Brodie couldn't control a bouncing puck at the blue line, and Nieto sped away on a breakaway that he finished with a top-shelf wrist shot.

However, Flames rookie Rasmus Andersson tied the score five minutes later on a power play, as Colorado's Derick Brassard made his third trip of the game to the penalty box. From the edge of crease, Sam Bennett sent a no-look back pass to Andersson at the other side of the net, and the rookie blue-liner made no mistake with the open net.

Then Sean Monahan gave the Flames their first lead with a Johnny-on-the-spot tally at 12:27 of the third period. After both Johnny Gaudreau and Bennett had their attempts blocked, Monahan chipped a high offering into the net.

But J.T. Compher's first NHL playoff goal with 2:39 remaining in regulation forced overtime. With the goalie already pulled for the extra attacker, Compher found a loose puck during a scramble and slipped it home.

Mike Smith made 36 saves for Calgary after making 26 in the Game 1 shutout.

The Avalanche could receive another boost before the next game as Cale Makar, a defenseman drafted fourth overall in 2017, is expected to join the squad now that his NCAA season with Massachusetts is done. The Avs may need him, as defenseman Samuel Girard left the game early in overtime after a check from Bennett.

--Field Level Media