Theodore made nine saves in the opening 20 minutes and 23 overall, backstopping Montreal's 4-1 victory over the Rangers that gave the Canadiens a split of the home-and-home series.
The Canadiens, who lost 5-2 Saturday in Montreal, have won six straight in New York -- including both meetings this season.
Theodore didn't make it past the first period at home. He was pulled after allowing three goals on 13 shots.
"The last game, as a team, myself, I didn't think we played the way we should," Theodore said. "I was unhappy with the way I played so today was a big challenge for us to play well and for me to bounce back."
Steve Begin scored a short-handed goal 1:14 after Jaromir Jagr tied it for New York in the third period and Alex Kovalev and Niklas Sundstrom padded the lead for the Canadiens, who have earned 11 of a possible 12 points away from home (5-0-1).
"I thought tonight was a solid, patient game and patience paid off," Canadiens coach Claude Julien said. "We got better, and in the third period we took advantage of our opportunities."
Saku Koivu gave Montreal a 1-0 lead with a power-play goal 47 seconds into the third period to break up a duel between the Rangers' Henrik Lundqvist and Theodore, who made 23 saves.
But Jagr answered at 9:40 with his NHL-best 12th goal, scored while the Rangers were on a 5-on-3 power play. He ripped a slap shot from between the circles as Begin dived in front of him in an attempt to block the drive. Jagr extended his point streak to 10 games, notching 10 goals and five assists in the run.
While the Canadiens were still killing off Theodore's delay-of-game penalty, Sundstrom sent Begin and Andrei Markov off on a 2-on-1 break. Begin held the puck as Marek Malik tried to disrupt the play and then rifled a high shot that beat Lundqvist's glove to make it 2-1 with 9:06 left.
"We really tried, but it seemed that we didn't play the way we really wanted to play," Lundqvist said. "We tied the game and then we made some easy mistakes."
Kovalev made it 3-1 with 3:46 left by scoring his fourth of the season, assisted by Koivu. Sundstrom sealed it with an empty-netter with 36.4 seconds remaining.
Koivu made it 1-0 when he deflected Craig Rivet's slap shot, fired from just inside the blue line. It got past Lundqvist, who was just under a minute away from helping the Rangers kill off Darius Kasparaitis' double minor for high-sticking.
Rivet heard boos all night from the Madison Square Garden crowd because of his hit Saturday in Montreal that left Rangers forward Martin Rucinsky with a sprained knee ligament that could keep him off the ice for a month.
"Actually I felt like I was back in Montreal because I hear that quite a bit there, too," Rivet said with a laugh. "I can understand the fans' frustration. They lost one of the best players in the league so far this year."
Theodore was sharp in the first - stopping Jagr twice on good scoring chances, and a hard shot from the slot by Blair Betts. His workload decreased the rest of the way as the Rangers found themselves constantly short-handed - including 8:44 of the second period and 15:31 overall.
"Any hope we had of creating momentum was certainly stunted by that," Rangers coach Tom Renney said.
New York was down two men for the first 57 seconds of Kasparaitis' penalty, and Lundqvist kept the game scoreless by fighting through screens to stop Montreal shots and grab several that struck him in the chest.
Lundqvist, who finished with 27 saves, was stellar until his rough third period. He entered his fourth straight start and eighth in nine games with the second best goals-against average in the NHL. But he is still considered Kevin Weekes' backup by Renney.
The Rangers were trying for their second three-game winning streak of the season after failing to notch one in 2003-04, but instead fell to 4-1-2 at home.
- Montreal (8-3-1) won eight October games for the fifth time in team history and first since 1991.
- The Canadiens outshot New York 40-29 Saturday.
- Rangers D Tom Poti sat out because of the flu, drawing cheers from the home crowd that has booed his play throughout the season.
- The teams will meet once more this season, March 11 in Montreal.
- Jagr's 549th career goal tied him with Ron Francis for 19th on the NHL list.