Brock Boeser scored, and Braden Holtby made 26 saves for the Canucks (6-9-0), who have lost four in a row, including 7-3 to the Maple Leafs here Thursday.
"When you have a bad game you've got to come out flying and be ready to play right from the start," Holtby said. "You never know if you're going to win or lose. But you need a response, and we don't have that yet. We've got to get on the same page. We're a disconnected group right now and it's showing. It's frustrating. If we want to be a good team, we've got to have everyone pulling the same rope. And that's what we work towards from now on."
The teams play again here Monday to end the three-game set.
Simmonds put the Maple Leafs up 1-0 at 4:42 of the first period with a power-play goal when he shot over Holtby's right shoulder from the left side of the crease. Marner assisted on the goal to extend his point streak to seven games (14 points; three goals, 11 assists).
"I've seen that goal a couple of times when he was with the Philadelphia Flyers, but that was really impressive to see with my own eyes tonight," Marner said.
Matthews made it 2-0 at 14:04 when got around Vancouver defenseman Jalen Chatfield in the slot and shot over Holtby's glove.
"He does [do things that surprise me] but I think that speaks to his ability and how special he is," Keefe said. "That goal, it happened so fast that I don't think anybody on the ice was really ready for it, just how quickly he went from going around a defender to putting it in the net. All season he's been really good for us, but these last two games, he's really had jump."