Clemmensen was outstanding for the Southeast leaders, and he outplayed Bryzgalov, who was the NHL's first star the past two weeks. Bryzgalov had 11 saves.
Clemmensen put Bryzgalov on notice there will be some competition for the honor this week. He stopped all 11 shots in the first period to set the tone and had 12 saves in the third to help the Panthers snap a five-game losing streak to the Flyers.
"I was fortunate to get a couple of saves under my belt, and I just went from there," Clemmensen said. "For me, it's a matter of getting into my comfort zone, getting into a flow. Certainly, experience helps you at this time of year, but it's never easy in this building. We'll definitely take this."
Bryzgalov was 8-0-1 with a 1.20 goals against average with four shutouts and a .960 save percentage to help the Flyers win three of four before Tuesday.
Bryzgalov got beat twice, but it was tough to completely blame the resurgent Russian for both goals.
Left alone in the slot, Weiss scored his 18th of the season on a wrist shot high over Bryzgalov for a 1-0 lead in the first.
Both teams were aided by a couple of bounces in the second period.
The Panthers struck first, when the puck bounced off the boards, slid past Flyers defenseman Braydon Coburn, and right to Bergenheim. He was uncovered during the power play and easily punched in his 17th goal.
The Panthers put another puck in the net, but this one helped the Flyers.
Wellwood's pass attempt to a charging Danny Briere ricocheted off Florida defenseman Ed Jovanovski's skate and straight into the net to make it 2-1.
The Flyers wouldn't get another break.
"I thought we came out a little bit sleepy in the second period for a few minutes," Flyers coach Peter Laviolette said. "They caught a really nice break off the carom off the glass. After that, I think we got back to work."
Clemmensen, once considered the heir apparent to Martin Brodeur in New Jersey, improved to 12-6-5 this season. He held off a flurry of shots in the final minutes to make the lead stick.
"We need everyone contributing, and we have that," Panthers coach Kevin Dineen said. "We have guys like Scott that are scratching and clawing to get in the lineup, and that showed out there. That's a product of work ethic, and he deserved the chance. He played well. He made a statement there."
The Flyers went 0 for 4 on the power play.
"I thought we played well, but at the same time, we have to drive to the net more, create more traffic in front, stuff like that, to make it harder for their goalie," Flyers forward Max Talbot said.
The Panthers won five straight games for the first time since their franchise-record, seven-game winning streak in 2008.
Pittsburgh's 8-4 win over Winnipeg on Tuesday gave the Penguins a four-point lead over the Flyers for fourth place in the Eastern Conference.
The Panthers bumped their lead to five points over Washington for first in the Southeast and kept their grasp on the third spot in the Eastern Conference. This is the latest the Panthers have been in first place.
The Flyers won the season series 3-1. ... The Flyers' penalty killers had been perfect in 11 of 12 games before allowing Bergenheim's goal. ... The Flyers snapped a five-game home winning streak. ... With 10 games left, Florida (85 points) has already surpassed its point total for the last two seasons.
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PHILADELPHIA, PA - MARCH 20: Sean Bergenheim #20 and goaltender Jose Theodore #60 of the Florida Panthers warm up...