LAS VEGAS -- The St. Louis Blues lost their first game without defenseman Jay Bouwmeester, 6-5 in overtime to the Vegas Golden Knights at T-Mobile Arena on Thursday.
Jonathan Marchessault scored his second goal of the game on the power play at 2:30 of overtime when he one-timed a pass from Mark Stone from the high slot.
"Obviously, it's tough. We all went through a lot," St. Louis center Ryan O'Reilly said. "You could tell we missed [Bouwmeester]. For myself, every game I've played here in the last year he's been here. It's weird not having him in the room."
[WATCH: All Blues vs. Golden Knights highlights]
Zach Sanford scored four goals for the Blues (32-15-10), who played for the first time since their game at the Anaheim Ducks on Tuesday was postponed after Bouwmeester had a cardiac episode on the bench during the first period.
"Obviously, I'd really want to have him here," Sanford said. "I think he was watching over tonight and maybe helping out a little bit too."
Video: STL@VGK: Sanford scores four goals vs. Golden Knights
Jordan Binnington made 46 saves for St. Louis, which has lost three games in a row (0-1-2) and leads the Colorado Avalanche by two points for first place in the Central Division.
Stone had four assists, and Max Pacioretty had two goals and an assist for the Golden Knights (29-22-8), who won for the first time in three games (1-1-1). Malcolm Subban made 19 saves in his first start since Jan. 31.
Vegas, which ended a four-game losing streak at home (0-3-1) in the first of a five-game homestand, is tied with the Edmonton Oilers for second place in the Pacific Division, three points behind the first-place Vancouver Canucks.
"I think as a team, we're trying to be successful at home," Marchessault said. "We're not necessarily getting the results we wanted. Right now, we have a nice homestand, and it's time to make a statement here."
Pacioretty and Sanford each scored two goals in the first period.
Sanford gave the Blues a 1-0 lead 25 seconds into the game, and Pacioretty tied it 1-1 on the power play at 1:59.
Pacioretty scored again at 6:34 to give the Golden Knights a 2-1 lead, but Sanford tied it 2-2 at 9:41.
Video: STL@VGK: Pacioretty buries PPG from the circle
Mackenzie MacEachern scored at 15:43 to give St. Louis a 3-2 lead.
Sanford completed his first NHL hat trick when he scored at 5:13 of the second to make it 4-2.
Marchessault cut it to 4-3 with a power-play goal at 18:59.
Nate Schmidt tied it 4-4 at 6:33 of the third period on Vegas' third power-play goal of the game.
"It's hard to come back on these teams," Schmidt said. "It'd be nice to get up on these guys and stay ahead, but we had a lot of resolve in our game tonight."
Sanford scored his fourth goal to give the Blues a 5-4 lead at 11:45, but Alex Tuch tied it 5-5 at 15:20 when he deflected Jon Merrill's wrist shot from the right point.
The Golden Knights went 4-for-5 on the power play. It was the first time they scored four power-play goals in a game since Dec. 19, 2017, against the Tampa Bay.
Video: STL@VGK: Tuch ties the game late with tip-in
Vegas was 3-for-26 on the power play since hiring Peter DeBoer as coach Jan. 15.
"I think we made a big emphasis making sure to move our feet and move the puck quickly, and that'll open up the seams," Pacioretty said, "and that's kind of what happened tonight."
They said it
"Just his presence alone is just a calming thing for our team, and you can tell we missed it tonight. Especially when you get leads like that and he's a guy that we rely on. It's a tough adjustment. Emotion was there, we just have to be better, a little more detailed with certain things." -- Blues forward Ryan O'Reilly on playing without defenseman Jay Bouwmeester
"We know the position we're in. We're battling for our lives. We know we had a letdown two games ago and dropped a point (a 6-5 overtime loss to the Carolina Hurricanes on Feb. 8) and had a tough game last game on the road (a 4-0 loss to the Minnesota Wild on Tuesday). It was an important game for our group to get back on it and make sure we're giving ourselves a chance here." -- Golden Knights forward Max Pacioretty
Video: Sanford gets his first career hat trick
Need to know
The Blues are the only team that has never lost to the Golden Knights in regulation (5-0-4). ... It was Sanford's second multigoal game in the NHL. He scored two goals Feb. 4 in a 6-3 win against the Carolina Hurricanes. ... Tuch, who played his 200th NHL game, left the game at 17:19 of the third period with a lower-body injury. ... DeBoer said goalie Marc-Andre Fleury (illness) is day to day. ... Vegas center William Karlsson had two assists, his first points since returning to the lineup against Minnesota after he missed the previous eight games with a broken finger. ... Golden Knights defenseman Shea Theodore had two assists, giving him an NHL career-high 39 points in 58 games (37 points in 79 games last season).
Video: EA Sports OT Winner: Marchessault wins it for Vegas
Blues: Host the Nashville Predators on Saturday (3 p.m. ET; FS-MW, FS-TN, NHL.TV)
Golden Knights: Host the New York Islanders on Saturday (10:30 p.m. ET; ESPN+, ATTSN-RM, MSG+, NHL.TV)
Video: Marchessault, Pacioretty each score twice in OT win