Charles Hudon and Jesperi Kotkaniemi also scored for the Canadiens (9-5-3), who snapped a two-game losing skid. Max Domi had two assists to extend his point streak to six games.
Goaltender Antti Niemi made 34 saves on 38 shots. Starter Carey Price served as Niemi’s backup after conceding at least four goals in four straight games.
Brad Hunt, Jonathan Marchessault, Alex Tuch and William Karlsson scored for the Golden Knights (7-9-1). Marc-Andre Fleury stopped 21-of-26 shots.
Pacioretty gets a standing ovation in return to Montreal:
Former Canadiens captain Pacioretty was kept off the score sheet despite taking nine shots on goal in his first game at the Bell Centre as a visiting player.
Pacioretty was dealt to the Golden Knights in the off-season in return for Tatar, prospect Nick Suzuki and a second-round draft pick. The 29-year-old was given a standing ovation following a video tribute prior to puck drop.