The Bruins (3-0-0) remained undefeated as they continue their four-game road trip to start the season, all against Western Conference teams. Boston has outscored Dallas, Arizona and Vegas 7-3, and won its first three games for the first time in the past 18 seasons.
Boston, which was 4-0-2 in the preseason, improved to 4-1-0 all-time vs. the Golden Knights.
Rask moved into sole possession of 49th place with his 267th career win. The 32-year-old goalie, one win shy of tying Don Beaupre, needed help off the ice at the conclusion of the game.
Marc-Andre Fleury made 31 saves but dropped to 12-8-5 against the Bruins with a .915 save percentage.
Vegas started out strong with back-to-back goals in the first period by Stone and Smith to take a 2-0 lead in the first 8:20.
But the defending Eastern Conference champions answered with four goals — three from their top line of Marchand, Pastrnak and Patrice Bergeron.
Marchand scored 33 seconds into the second period to put Boston ahead 3-2, handing Vegas its first deficit of the young season.
The Golden Knights, who didn’t get their first shot on goal in the third period until there was 8:28 left in the game, made it a one-goal game when Pacioretty beat Rusk with his first of the season, a power-play goal with 5:18 remaining.
NOTES: Bruins captain Zdeno Chara, 42, appeared in his 1,488th game, breaking a tie with Wayne Gretzky for the 23rd-most in history. … Chara and San Jose’s Joe Thornton, 40, are the two oldest active NHL players. They both made their debut in 1997 and are the only active players who played a game in the 1990s. … The Golden Knights were one of three teams entering Tuesday that had yet to allow a power-play goal, along with Carolina and the Rangers. Both Carolina and Vegas allowed power-play goals in their respective games.
Bruins: At the Colorado Avalanche on Thursday.
Golden Knights: At the Arizona Coyotes on Thursday.
Source: Fox Sports