Archibald set up Sheahan on a 2-on-1 at 7:48 of the third period to give Edmonton a 4-3 lead. It was Archibald's first multipoint game of the season.
Ryan Nugent-Hopkins was awarded a goal at 7:00, but after review it was determined the puck hit the crossbar and did not cross the goal line.
"It felt really good. Sheahan and I have been clicking a little bit as a line," Archibald said. "To be able to put a couple on the board felt really good. We've been playing well lately, but the small things have been hurting us. To have a comeback game like we did tonight and have a full 60 was a good feeling."
Max Domi scored for Montreal to tie it 3-3 at 1:09 of the third, getting around Edmonton defenseman Darnell Nurse on a 1-on-1.
"I think the first half of the first they were all over us and I thought we woke up and were better in the second half of the first, and then in the second half of the game we were better," Canadiens captain Shea Weber said. "Then the third was pretty even. It was a little bit of a tough bounce on that high flip and they score on another odd-man rush. Other than that, I thought we did a great job to fight back. It was a little bit of a slow start, which wasn't what we wanted, but there was a lot of fight to keep coming back and we just let it slip away at the end."
Draisaitl scored 1:30 into the first period, off a pass from McDavid on a 2-on-1 to give Edmonton a 1-0 lead. Archibald made it 2-0 at 11:51, redirecting a pass from Ethan Bear.
"We beat ourselves," Canadiens coach Claude Julien said. "There were some really bad penalties in the offensive zone at bad times and some real bad decisions. Two 2-on-1 goals, and I didn't think we were sharp tonight, simple as that. We battled back, and you're seeing a team that never gave up, but at the end we only have ourselves to look at. We beat ourselves."
Petry scored shorthanded at 14:19 to make it 2-1. He collected an errant pass off the boards in his zone, skated down the left wing and shot the puck over Koskinen's shoulder.
Phillip Danault tied it 2-2 on the power play at 8:29 of the second period with a deflection of a point shot by Petry. McDavid scored on the power play at 15:40 to give Edmonton a 3-2 lead.
"Having the early lead is better than the other way around, where you are chasing it, especially tonight," Oilers coach Dave Tippett said. "It was imperative for us [to get the lead] in a back-to-back like this, because you use a lot of energy when you are chasing a game. Tonight we didn't chase the game at all. We were even at times, but we had control of it rather than using extra energy trying to get something back."
