Lundqvist made 29 saves, including Marco Sturm's first-period penalty shot, holding the Bruins scoreless until late in the game to lift surging Rangers to a 3-1 win on Saturday afternoon.
"That was a game-changer right there," said Brandon Dubinsky, who had a goal and assisted on the other two. "It always changes the dynamic of the game."
With the Rangers holding a 1-0 lead, Sturm was tripped by Ales Kotalik on a breakaway.
The sellout crowd was roaring, but the Rangers' netminder made a pad save when Sturm fired a wrister looking to go between the legs.
"There's no doubt that would have gotten us back in the game, but it didn't happen," Boston coach Claude Julien said.
New York won for the eighth time in 12 games (8-1-3) and sent Boston to its third loss in four after a thrilling overtime win over the Flyers in the Winter Classic at Fenway Park on New Year's Day.
"It's a big play, it gets the bench going. You go out and start playing again, you're still up, you haven't given up the goal," Rangers coach John Tortorella said of Lundqvist's save on Sturm.
The Bruins, already without center Patrice Bergeron who is sidelined with a fractured thumb, lost another playmaker, Marc Savard, for three to four weeks with partial ligament tear in his right knee on Thursday night.
"If [the injuries] are affecting psyches, we have to find a way to get around it quickly," Boston goaltender Tim Thomas said.
Dennis Wideman broke the shutout with 3:44 left.
The Rangers have won all three meetings against Boston this season, including a 3-2 win at Madison Square Garden on Monday.
"When you win, you get more confidence," Lundqvist said. "A lot of good things are happening right now."
Thomas stopped 31 shots for Boston.
The Bruins posted shutouts against the Rangers the past two times the teams played in Boston, but New York grabbed a 1-0 lead when Del Zotto cut down the left wing, slipped around defenseman Zdeno Chara and slipped a backhander between Thomas' pads 7:56 into the game.
New York, which outshot Boston 21-3 in the second, made it 2-0 midway into the period when Dubinsky scored off a rebound directly in front on Thomas. Dubinsky, a center, was moved to wing six games ago.
After New York took control in the third, the TD Garden crowd was very quiet and a chant of 'Let's Go Rangers' could be easily heard echoing through the building.
"When you play with a lineup you have right now, you almost have to play a perfect game," Julien said.
Christensen scored on a wrister from the right circle 37 seconds into the third. He has three goals and three assists in his last seven games. The Rangers picked him up off waivers from Anaheim on Dec. 2.
Boston pulled Thomas for an extra skater with about 1:40 to play and the Rangers hit the outside of the post twice on long shots.
- It was Sturm's fourth career penalty shot with the Bruins, the most ever. He's 1 for 4.
- Rangers D Michal Rozsival played his 600th NHL game.
- Julien's next win will tie him for eighth place on the Bruins' career list with Lynn Patrick at 117.