Johnny Gaudreau highlighted his return to Boston with an early goal and Dan Vladar made 27 saves to shut out his former team as the Calgary Flames blanked the host Bruins 4-0 on Sunday night.

Gaudreau, who won the Hobey Baker Award in 2014 while playing at nearby Boston College, registered his team-leading 22nd point with his eighth goal of the season just 1:29 into the game.

Noah Hanifin, Andrew Mangiapane and Mikael Backlund also scored goals for Calgary, which earned its third straight win. Mangiapane's goal was his 15th of the season to break a tie with Alex Ovechkin for second-most in the NHL.

Vladar improved to 4-0-1 with his second shutout of the season and the Flames' seventh in 19 games. The 24-year-old was drafted in the third round of the 2015 draft by the Bruins and made his NHL debut with the team last season.

Boston dealt Vladar to Calgary for a 2022 third-round pick over the offseason.

Bruins rookie goalie Jeremy Swayman stopped 27 of 31 shots and suffered his first career home loss. The 22-year-old entered 8-0-0 with a .945 save percentage and a 1.24 goals-against average at home over parts of two seasons.

The Bruins had won three straight and six of their last eight games. The loss was just Boston's second at home this season (6-2-0).

Gaudreau put Calgary up 1-0 in the opening period after sending home a rebound from the right circle after Juuso Valimaki's shot from the left circle bounced right to him off Swayman's blocker.

Hanifan doubled the Flames' lead with his first tally of the season at 13:51 of the second. Matthew Tkachuk's shot from the half wall deflected off Swayman's pads and Hanifin finished it off after skating in from the left circle.

Mangiapane lit the lamp for the 14th time away from home this season with a short-handed goal 3:08 into the third. Backlund added his fourth goal of the year just over a minute later.