Fleury posted his second shutout of the season and 13th of his career, while Chris Minard and Tyler Kennedy each added a goal for Pittsburgh, which altered its style to the more defensive-oriented 1-4 after a recent stretch of losing seven of eight.
"I think this was similar to last game and the (win against Philadelphia on Tuesday)," Fleury said. "The guys did a great job of not giving them too many scoring chances and we got some turnovers, got chances. We got some goals early, so that was a big game for us."
The Penguins have won three of their last four games and moved back into playoff position in the Eastern Conference.
Crosby was back in the lineup after sitting out Friday's game with an apparent knee injury. He missed a penalty shot early in the second period and saw his five-game scoring streak end. Crosby was hurt during Wednesday's loss to Washington.
"The leg felt pretty good," he said. "Hopefully it's better, but we'll see tomorrow."
The Rangers' three-game winning streak ended as they were shut out for the third time this season. New York hasn't won in regulation at Mellon Arena in the past 12 games, including playoffs.
"That little extra intensity wasn't really there for us," New York goalie Henrik Lundqvist said. "I think the way they played, they made it pretty tough for us to get that edge. They slowed it down and just were waiting for mistakes. If we had gotten the first goal, maybe it's a different game, but once they got a 2-0 lead they played smart after that."
Fleury has allowed only one goal in his past two games. The Penguins traded for Mahieu Garon on Saturday to perhaps push Fleury, the No. 1 overall pick in the 2003 draft who has been spectacular at times but inconsistent at others.
Fleury had a 2.94 goals-against average and .905 save percentage and had given up at least four goals during seven of his past 17 starts, causing Penguins coach Michel Therrien to publicly question his team's goaltending.
"He played well (Sunday)," Therrien said. "I like the way he was focused. I like the way he's square to the puck. He doesn't have to make spectacular saves and that's a great sign because of his position. If you want to win in this league, you need great goaltending. And he did a great job again today."
Fleury donned a Steelers helmet and waved a Terrible Towel when he was announced as the game's No. 1 star. Across town, the Steelers were to host the AFC Championship game hours later.
"He played a strong game, but I don't think we tested him enough," Naslund said. "I don't think we got in to get real quality chances. He was strong, but I think we didn't have our 'A' game."
Minard scored his first of the season on a one-timer from the slot off a pass from Sykora 7:35 into the game.
"It gets everybody going when you get an early lead," said Minard, who was playing in his 12th game this season, bouncing back and forth from the minors. "Then you can play your game and get the crowd into it."
Kennedy made it 2-0 eight minutes later when he skated in from the right point and fired a wrist shot from the inner edge of the top of the faceoff circle, beating Lundqvist for his eighth of the season -- but first at home.
Sykora's 17th goal came on the power play 7:32 into the second. Jordan Staal won a faceoff in his own end back to Ryan Whitney, who carried the puck out of his zone and found Sykora, who was behind the defense and beat Lundqvist with a wrist shot.
"We got some big goals, (Fleury) played great, we didn't give up a ton of scoring chances, and when we did he was there to shut the door," Crosby said.
- The Penguins said C Mike Zigomanis is out for the season after he underwent surgery on his right shoulder.
- Also returning to the Penguins lineup after missing Friday's game due to injury were D Kris Letang and D Rob Scuderi . Pittsburgh D Brooks Orpik missed the game after leaving Friday's contest due to an unspecified injury.
- Kennedy's previous goal at home was March 16 against Philadelphia.