"I think overtime is a crapshoot, especially 3-on-3," Stastny said. "You might as well go out there and play aggressive. You could play a five-minute overtime and not have one chance either way and just sit back, or once there's one chance you can just kind of trade chances.
"Sometimes it's a coach's nightmare, a goalie's nightmare. But for the fans and the players, it's always fun going 3-on-3 and knowing any time you're out there it could end real quick."
Nick Suzuki scored for the Canadiens (9-6-5), who lost their fifth straight game (0-2-3). Allen made 19 saves.
"I just thought it was an attitude adjustment," Allen said. "We had a good day at practice yesterday and a good skate today and mood in the room and good attitude tonight. Obviously we did a few things structurally that got in and our offensive zone game was great, and we're going to get better."
Ehlers scored on a wrist shot from beyond the circles on a power play at 10:38 of the second period to give the Jets a 1-0 lead.