Plekanec deflected a shot by the 6-foot-6 son of former NHL defenceman Mark Tinordi past Johan Hedberg at 6:49 after the goalie made an ill-advised clearing attempt from behind his net. Tinordi got the puck above the left circle and let it fly.
Colby Armstrong also scored for Montreal, and Carey Price made 32 saves. The Canadiens moved into a tie with Pittsburgh for the most points in the Eastern Conference.
Defenceman Peter Harrold scored for New Jersey, which lost for the second time in two nights (0-1-1).
I don't think it's really truly going to sink in until we drop the puck, to be honest. I know there's going to be a lot of smoke and mirrors with the media attention and all that. We came [Monday] and it was sort of a light day to get things organized. We just want to focus in on the business aspect, the game itself. That's what we're preparing to do. Get these next couple of days out of the way and it's game on.
— Lightning captain Steven Stamkos on playing in his first Stanley Cup Final