Nittymaki left the game because of what general manager Paul Holmgren described as a slight hip strain.
"I felt a little sore the whole game, more and more every time I went down," Nittymaki said. "I felt it was better to be safe than sorry."
Esche, returning to action after missing 11 games following groin surgery, stopped 8-of-9 shots in the third.
Captain Peter Forsberg was also back in the lineup for the Flyers after missing the last three games because of a concussion. He had a couple good scoring chances but no points.
"It's been a while since I've been on the ice. I couldn't move for the longest time there," Forsberg said. "But it's good to be back. It's just too bad we didn't win the game."
The Flyers had some good opportunities, including a five-on-three for 1:04 late in the third period.
"I thought we battled pretty hard," Forsberg said. "But we've got to battle a little harder if we're going to win some games."
Olesz opened the scoring after poking the puck away from defenseman Alexei Zhitnik from behind. The puck bounced off Gelinas skate and back to Olesz, who was alone in front of the net and beat Niittymaki with a quick deke to his forehand.
Stumpel made it 2-0 at 3:40 of the second when he tipped in Gelinas' slap shot from the point.
"That goal real early helped, it kind of put them in a little bit of a hole," said Panthers defenseman Jay Bouwmeester.
Calder got Philadelphia's only goal on the power play at 18:16 of the second. His pass across the crease went in off the left skate of Belfour.
Van Ryn gave Florida a two-goal lead again when he beat Esche with a slap shot off a faceoff at 8:59 of the third.
"We got some big saves from Eddie tonight when we needed to," Florida coach Jacques Martin said. "I'm sure he'd like to have the goal back that went in. He has that ability after a goal to shut it down."
The Flyers are now 0-20-1 when trailing after two periods and 1-20-1 when the opponent scores first. ... Panthers center Olli Jokinen and right winger Nathan Horton both had five-game points streaks snapped. ... This was the first game of a season-long eight-game road trip for the Flyers. ... Florida placed center Stephen Weiss (shoulder) on the injury list, retroactive to Dec. 12, and recalled left winger David Booth from AHL Rochester.
Copyright by STATS LLC and The Associated Press
Arena: BB&T Center Location: Sunrise, Florida
Referees: Don Koharski, Rob Martell Linesmen: Scott Driscoll, Mark Shewchyk
Attendance: 17,771 (92.3% full)
Team Stat Comparison
Power Play Goals
Power Play Opportunities
Shots on Goal
Rostislav Olesz (5)
Assist: Martin Gelinas
Jozef Stumpel (10)
Assists: Martin Gelinas, Rostislav Olesz
Kyle Calder (3)
(Power Play) Assists: Randy Jones, Jeff Carter
Mike Van Ryn (3)
Assists: Victor Uchevatov, Chris Gratton