Olli Jokinen scored the game-winning goal late in the second period and Florida beat Philadelphia 3-2 on Friday night, the Flyers' fifth straight loss.
Belfour had 25 saves for the Panthers, who started the season 4-0 at home for the first time since 1995-96, when they made it to the Stanley Cup finals. Belfour, who signed as a free agent before the season, improved to 1-2-0 this season.
"I was in the right spots to make the right plays," Belfour said. "We knew they were going to come hard and we tried to match that."
"These ones hurt, they hurt a lot," Flyers coach Ken Hitchcock said. "We are 1-6-1 and we played seven hard games. It's tough on everybody right now."
Mike Van Ryn passed across the ice to Jokinen in the last seconds of a power play, whose shot from the right of the crease got past Niittymaki's glove with 1:43 left in the middle period to break a 2-2 tie.
Jokinen's game-winning goal is his 24th with Florida, breaking the franchise record previously held by Pavel Bure.
"It was a pretty even game but it was good to get Eddie that first win," Jokinen said. "We worked hard against a team we've struggled against. We deserve the two points."
Gagne's second goal came 6:38 into the second period after a shot by Sami Kapanen was blocked by Belfour. Gagne got the rebound and poked the puck into the net to give the Flyers a 2-1 lead.
The Panthers tied it 34 seconds later when Kolnik's shot from the top of the right circle beat Niittymaki on the glove side.
"We lost five in a row and you cannot get used to it," Gagne said. "Right now, we're in a very deep hole. I don't remember, on my side, the last time I've been there."
The Panthers scored on their first shot on goal. During a Flyers power play, Stumpel picked up a loose puck at center ice and his shot from the slot went through Niittymaki's legs for a shorthanded goal 2:01 into the game.
Philadelphia tied it at 1 at 16:45 of the period when Mike Knuble passed across the front of the crease to Gagne on the right side and he put the pack past Belfour on the glove side.
"This is a good win," Panthers coach Jacques Martin said. "The Flyers are a gritty team trying to work their way out of where they are now. We had a good start and Eddie was really strong."
Florida is 1-9-1 at home against Philadelphia since Jan. 17, 2000. ... Jokinen has 266 points as a Panther, which ties him for fourth place on the franchise list with Rob Niedermayer. ... Florida forward Todd Bertuzzi was scratched because of back spasms. ... Philadelphia forward Peter Forsberg missed the game after spraining his left wrist on Thursday at Tampa Bay.