Boo Nieves, Jesper Fast, Mats Zuccarello and Pavel Buchnevich scored in support of Pavelec, who drew the spot start because Lundqvist had the flu. Buchnevich provided the game-winner when his centering pass deflected off Pittsburgh's Kris Letang and by Tristan Jarry 11:12 into the third period.
Phil Kessel picked up his team-high 13th goal for the Penguins. Conor Sheary added his ninth and Patric Hornqvist his 11th for Pittsburgh, which saw its season-high four-game winning streak snapped. Jarry finished with 25 saves but could only watch the puck smack off Letang's stick and flutter by to give the Rangers the lead for good.
Penguins captain Sidney Crosby was held scoreless as his streak of five straight multipoint games ended.
Two of the marquee franchises in the competitive Metropolitan Division are starting to find their footing after bumpy starts. New York and Pittsburgh both came in 4-1 over their last five games thanks to resurgent play by their stars.
For a night, however, the Rangers had to find a way to make do without Lundqvist, who has emerged from an early season funk to lift the Rangers back into contention but was a surprise scratch a few hours before the opening faceoff. Enter Pavelec, just 2-13-1 with a 4.20 goals against average in his career against Pittsburgh.
New York controlled play but Sheary gave the Penguins a 1-0 lead when he took a pass from Patric Hornqvist and pounded it by Pavelec 15:13 into the first for his ninth goal of the season. The Rangers tied it just over 90 seconds later when Nieves beat Jarry with a wrist shot from the top of the right circle for the first goal of his career.
Pittsburgh regrouped from a sleepy first period to dominate the second, pumping 23 shots at Pavelec. New York, however, counterpunched expertly. Kessel's wrist shot from the slot 7:11 put the Penguins back in front but a rebound at the end of an odd-man rush by Fast and a knuckling shot off Zuccarello's stick handcuff gave the Rangers a 3-2 lead after two.
Hornqvist took a perfect stretch pass from Evgeni Malkin and beat Pavelec on a breakaway 3:35 into the third. The Penguins had several chances to go ahead but were held in check by Pavelec and a bit of bad luck. Pittsburgh hit at least four posts and the Rangers took advantage of the reprieve.
Notes: Penguins D Justin Schultz left in the first period with an apparent lower body injury. He returned briefly in the second and did not play in the third. The Rangers called up Alexandar Georgiev from their AHL affiliate to serve as Pavelec's backup with Lundqvist unavailable. New York also scratched D Steven Kampfer. The Penguins scratched D Chad Ruhwedel and Fs Greg McKegg and Josh Archibald. New York's Michael Grabner played in his 500th career game.