Pack your flippers and goggles.

Nathan MacKinnon is the Missy Franklin of this Stanley Cup tournament.

Who else could lift 18,000 Avalanche faithful off their seats with a goal so impossible it took a half-dozen slow-mo replays to figure out exactly how he pulled it off? No. 29. That’s who.

The Avalanche erased a 3-0 deficit to beat the Minnesota Wild 4-3 in overtime at Ball Arena on Wednesday in one of the wildest comebacks since the team arrived here in 1995. The loud, proud triumph clinched the series, 4-1.

“I wish it was easier. That one was something,” Avalanche coach Jared Bednar said with a grin.

And it was MacKinnon’s game-tying goal with 1 minute, 23 seconds left in regulation that completed the comeback and helped move the Avalanche into the Western Conference finals.

He gathered a pass from Martin Necas. His stick went tap-tap-tap. Then it went boom, blasting the puck over the broad right shoulder of Minnesota goalie Jesper Wallstedt and just inside the near post of the net.…