Bo Horvat scored twice for the Vancouver Canucks in a 5-2 win against the St. Louis Blues in Game 1 of the Western Conference First Round at Rogers Place in Edmonton on Wednesday.
Elias Pettersson, Troy Stecher and J.T. Miller scored, and Jacob Markstrom made 29 saves for Vancouver, the No. 5 seed in the West.
"You want to get up for the big games, you want to be a difference maker, especially at this time of year," Horvat said. "You're playing the Stanley Cup champs, it's easy to get up for. These are the games you want to win."
Teams that win Game 1 are 478-219 (68.6 percent) winning a best-of-7 NHL Stanley Cup Playoff series. Game 2 will be in Edmonton, the Western hub city, on Friday (6:30 p.m. ET; NHLN, SN, FS-MW).
David Perron and Jaden Schwartz scored for St. Louis. Jordan Binnington allowed five goals on 22 shots. The Blues, who won the Stanley Cup last season, lost three straight games in the round-robin portion of the Stanley Cup Qualifiers to enter the playoffs as the No. 4 seed in the West.
"We didn't think we were going to walk over anyone here," Perron said. "They're a good team. They played a good game. They have a good power play, obviously. We tried to match that. I thought the intensity and compete level was there. We talked about raising that. We didn't enough, but it's a good step."
[WATCH: All Canucks vs. Blues Game 1 highlights]
Stecher, whose dad died on Father's Day in June, gave Vancouver a 3-2 lead at 5:37 of the third period.
"Obviously, I had a couple seconds there to reflect on my dad, and the biggest thing is everybody showed support on the bench instantly and kind of gave me a tap, and it just kind of motivated me to keep going," Stecher said. "Winning definitely helps."
Horvat skated around Blues defenseman Vince Dunn and scored from in close for a 4-2 lead at 8:01.
Miller scored the Canucks' third power-play goal of the game with 40 seconds remaining for the 5-2 final.
The Blues have been outscored 9-0 in the third period in the postseason.
"We know we have to be better in the third," St. Louis forward Brayden Schenn said. "Obviously not good enough. We'll find ways to continue to build and try and score some goals here. It's not the result we wanted."
Schwartz scored on a breakaway at 9:49 of the second period to tie the game 2-2.
"Listen, the game is right there, we didn't get the next goal," Blues coach Craig Berube said. "We've got to do a better job of not allowing what happened happen."
Video: Horvat scores twice as Canucks down Blues, 5-2
Horvat gave Vancouver a 1-0 lead with a power-play goal at 4:29 of the first period. Perron tied it 1-1 with a power-play goal at 16:37 on a one-timer from the right face-off circle.
Pettersson scored a power-play goal on a rebound to give the Canucks a 2-1 lead at 8:37 of the second period.
"We practice power play a lot," Pettersson said. "Today, we had three goals on the power play. It's huge for us. It's a good weapon to have and it can win us games."
It was the fourth straight win for Vancouver, which defeated the Minnesota Wild in four games in a best-of-5 qualifier series after losing the opener.
"This series is not going to be easy," Markstrom said. "It's going to be really tough. St. Louis is a great team, and we have to count on them coming really hungry for Game 2, and we have to step up our game as well and grow and keep building on what we started."
NOTES: Rookie defenseman Quinn Hughes had an assist on Horvat's first goal to extend his point streak to four games (one goal, six assists). … Canucks forward Tyler Toffoli (unfit to play) missed his fourth straight game. … Blues forwards Sammy Blais and Alexander Steen were scratched, and Berube said each is day to day.
NHL.com senior writer Dan Rosen contributed to this report