The Bruins improved to 18-13-0 with a win on the first stop of their three-game road trip that now winds through the frigid outposts of Winnipeg, Manitoba (Thursday) and St. Paul (Sunday).
After being stymied by Blues goalie Joel Hofer for the first 30 minutes, the Bruins got greasy goals from Minten and Kastelic in the second to surge to a 2-1 lead.
“We were all over him for the first 30 minutes I feel like, but really didn’t get much because he saw everything,” said Kastelic. “So, usually with every goalie, I think we need to make a good effort to try to get in front of his eyes and really make life difficult for them, and that’s just going to be our bread and butter going forward.”
Get Starting Point
A guide through the most important stories of the morning, delivered Monday through Friday.
Robert Thomas scored his second for the Blues (11-13-7) early in the third, but the Bruins answered quickly from Kastelic and Minten (the sixth of the season for both) to thwart the comeback hopes.
The first 20 minutes, however, were all about the goalies, with Hofer and Jeremy Swayman trading big save after big save.
Swayman (24 saves) was tested early — as in 14 seconds early.
The Blues worked the puck into the Bruins’ end on the opening face-off with Brayden Schenn dishing to Mathieu Joseph, who dumped one on the alert Swayman.
The Bruins answered with a threat of their own with Viktor Arvidsson landing a ripper on Hofer from between the dots off a slick pass from Zacha.
A pinch-in by Nikita Zadorov proved costly when the Blues were able to send Nick Bjugstad in on a partial breakaway where Zacha was forced to slash him to prevent a quality bid.
The Blues cashed in on the ensuing power play when Robert Thomas slammed a half-slapper past Swayman to cap a give-and-go with Pavel Buchnevich.
With Casey Mittelstadt and Logan Mailloux off with matching roughing minors, the Blues earned a four-on-three power play when Hampus Lindholm took down Thomas at the Blues blue line.
The Bruins were tighter on the kill, squashing it with Swayman standing tall.
The visitors earned a power-play with just four seconds left in the period when Bjugstad got the stick up high on Morgan Geekie.
They weren’t able to capitalize on the power play though they generated a few decent chances, none better than Geekie’s scorching double doinker (off the crossbar and post) that Hofer never saw.
Still, the man advantage buoyed the Bruins, who dominated territorially, outshooting and outscoring the Blues to take a 2-1 lead after 40 minutes.
It could have been worse for the hosts if not for the play of Hofer, who came up with several dandies despite being under siege for most of the period.
Shortly after the Blues tried to rile up the crowd using a hype video staring St. Louis native and Celtics star Jayson Tatum (that’s dirty pool!), the Bruins struck for a pair of goals.
Following a traffic jam in front of Hofer that included bids by David Pastrnak, who returned to the lineup after missing the previous five games with a lower-body injury, and Marat Khusnutdinov, the puck squirted to Minten. He slammed it into the open net for his fifth of the season and second in two games.
Not long after, Victor Soderstrom, playing in his third game as a Bruin, tossed one from the blue line that Kastelic redirected past Hofer for his first.
That gave the Bruins a 2-1 lead and set the stage for the wild third that included a Blues comeback followed by three unanswered Bruins goals.
Kastelic continues to put his imprint on game after game no matter where he’s slotted in the lineup.
“It’s definitely just really fun playing hockey right now,” he said. “I think it doesn’t really matter who I’m playing with and or where in the lineup you are. Everybody’s valued here, so that’s the biggest thing. So yeah, just having a blast right now and the wins have been fun, too.”
Jim McBride can be reached at james.mcbride@globe.com. Follow him @globejimmcbride.