ST. LOUIS -- The Vegas Golden Knights failed to clinch a berth in the Stanley Cup Playoffs, losing 3-1 to the St. Louis Blues at Enterprise Center on Monday.
The Golden Knights (42-28-6), who reached the 2018 Stanley Cup Final in their inaugural season, need one point to clinch. They are five points behind the San Jose Sharks for second place in the Pacific Division.
William Karlsson scored, and Malcolm Subban made 19 saves for Vegas, which is 10-2-1 in its past 13 games.
[WATCH: All Golden Knights vs. Blues highlights]
"I thought it was a good game, good hockey game by both teams," Golden Knights coach Gerard Gallant said. "Obviously they got the three goals and beat us tonight, but I thought we played well. We made a couple mistakes that ended in the back of our net, but there wasn't a lot of room out there. It was a playoff atmosphere type of game and they played really well."
St. Louis (41-27-8), which swept a four-game homestand, remained two points behind the Nashville Predators for second place in the Central Division and moved within four points of the first-place Winnipeg Jets. Nashville defeated the Minnesota 1-0 on Monday; Winnipeg lost 5-2 to the Dallas Stars.
Video: VGK@STL: O'Reilly scores off stretch pass
St. Louis has won 11 of 13 at home after starting the season 10-13-2.
"This homestand's been pretty good," Blues defenseman Jay Bouwmeester said. "We haven't been great at home all year. I think to have a four-game stretch like this at home, still trying to push and get ready for the playoffs, that's pretty big because you know that's going to be pretty big in a series like that.
"The last two games, you knew there were really good teams coming in. I thought we played pretty well. You're never going to play a perfect game and they're going to get chances. They are who they are, but I thought we handled it pretty well."
Zach Sanford had a goal and an assist, and Jordan Binnington made 24 saves for the Blues, who are 5-0-1 in their past six games.
"Looking at our roster coming into the season, everyone knew we were going to have a really strong team," Sanford said. "It just took us a little while to put it together. I don't think any of us are too surprised that we're here."
Ivan Barbashev's fourth goal and fifth point in three games gave St. Louis a 1-0 lead at 18:41 of the first period after Subban turned the puck over to Sanford.
Video: VGK@STL: Sanford, Barbashev connect for tally
"I was a little surprised," Barbashev said. "I was trying to shoot on the short side, and somehow it got in between his arm and the body and it just went in. I saw the replay and I was a little surprised."
Karlsson's power-play goal at 15:12 of the second period, the fourth allowed by the Blues in 47 attempts, tied the game 1-1.
Ryan O'Reilly's first goal in nine games and 27th this season gave the Blues a 2-1 lead at 18:14 of the second.
"It was nice to get on the board," O'Reilly said. "I haven't been shooting the puck very well lately and obviously [Bouwmeester] made just a great pass to set me up there. The goal came at a good time."
Sanford scored at 6:27 of the third period for the 3-1 final.
The Blues held the Golden Knights to their lowest shot total (25) in 19 games.
"I think it was both sides," Vegas forward Jonathan Marchessault said. "I think it was a tight game in the neutral zone. I think both teams played well and managed the puck well. We made like two or three mistakes out there and they cashed in."
Video: VGK@STL: Karlsson buries rebound on power play
They said it
"It's tough, especially to give up the first goal that I gave up. It's tough in a game like that. There's not too many chances going both ways, so it's costly to be giving up goals in these games." -- Golden Knights goalie Malcolm Subban
"Obviously if you look at these last four games, it's been good. We've found a way to win games and coming into the end of the year, that's what we want. We want this to be a tough building to play in, and it's good. We've got to keep building. We're not done yet. Get a good day off and get back to work." -- Blues center Ryan O'Reilly
Need to know
Golden Knights defenseman Shea Theodore (illness) was a late scratch. ... Marchessault had an assist, his 200th NHL point. ... Blues defenseman Alex Pietrangelo collected his 300th NHL assist. ... The Blues won all three games against the Golden Knights this season and are 4-0-2 against them since Vegas entered the League at the start of last season.
Golden Knights: At the Colorado Avalanche on Wednesday (10 p.m. ET; NBCSN)
Blues: At the New York Rangers on Friday (7 p.m. ET; MSG, FS-MW+, NHL.TV)
Video: O'Reilly, Blues defeat Vegas for fourth straight win