Gaborik broke free and outraced Andrew Ference and Johnny Boychuk down the ice. His first shot was blocked by goalie Tuukka Rask, but Gaborik batted the rebound out of the air to end the game and start a cascade of flying hats onto the ice.
Taylor Pyatt also scored for the Rangers (2-1), who squandered leads of 2-0 and 3-2 en route to avenging a season-opening loss at Boston on Saturday. Henrik Lundqvist made 26 saves for the win.
The Bruins fell to 2-1 in their first road game of the season.