Canada’s Kaiden Guhle and Austria’s Benjamin Nissner exchanged markers less than a minute apart midway through the frame, but Mangiapane earned a plus at 13:29 when teammate Bowen Byram’s point shot sailed into the net off an Austrian’s posterior.
The Canadian attack was just as relentless in period two, as Jared McCann, Connor Bedard and Pierre-Luc Dubois each found the back of the net.
Mangiapane came close to earning a second assist in period two, but his setup to Cozens late in the frame went for naught when the Buffalo Sabres winger cranked a snapshot off the crossbar.
But the third period told a completely different tale than the first two.
Nine Austrian shots.
Five Austrian goals, including a last-gasp equalizer from Marco Rossi in the final minute of regulation time - stunning the Canadian players and faithful alike.
By the time the puck was dropped in overtime, Canadian captain John Tavares had seen enough.
The Maple Leafs forward cruised through the neutral zone, then ripped a snapshot past the blocker hand of Austrian netminder David Madlener to secure the extra point for Canada, and prevent Austria from completing a comeback for the ages.
Mangiapane played 16:15 Tuesday, his 22 shifts were the most of any Canadian forward.
Canada outshot Austria 49-21, and finish the day tied with Switzerland atop Group A with eight points.
