Bo Horvat scored twice and the Vancouver Canucks beat the defending Stanley Cup champion St. Louis Blues 5-2 on Wednesday in the opening game of their best-of-seven first-round series.

J.T. Miller, Elias Pettersson and Troy Stecher also scored for Vancouver.

David Perron and Jaden Schwartz scored for St. Louis.

Horvat has four goals in return-to-play action while rookie teammate Quinn Hughes logged an assist to reach seven points (one goal, six helpers) in five games.

Stecher broke a 2-2 tie in the third period when he raced down the right-wing and sent a slap shot from the circle under the arm of St. Louis goalie Jordan Binnington.

Jacob Markstrom made 29 stops for the win.

The Canucks were making their first playoff appearance since 2015, having defeated the Minnesota Wild in the qualifying round.

They never trailed in the game.

The teams swapped mirror-image power-play goals in the first period.

Horvat opened the scoring about five minutes in when he one-timed a feed from Hughes from the top of the left circle past Binnington.

St. Louis countered with under four minutes to go. Perron slapped a pass from Brayden Schenn from the top of the right circle high over the glove of Markstrom.

Vancouver regained the lead on the power play midway through the second period. Pettersson whipped the puck under the bar off a goalmouth scramble for his second goal.

The Blues tied it just over a minute later when Schwartz tipped the puck past pinching Canuck defenseman Chris Tanev at the Blues' blue line, then charged in on a breakaway and beat Markstrom with a nifty backhander through the pads.

After Stetcher's goal, Horvat turned Blues defenseman Vince Dunn inside out, raced in and fired a wrist shot past Binnington on the blocker side.

Miller added the fifth goal on the power play with less than 40 seconds left.

Game 2 is set for Friday night.