PHILADELPHIA — Travis Konecny had a reason to smile as he held a souvenir puck.

His first career NHL goal snapped the Flyers from lethargic to lively and gave Konecny a good reason to call home.

"My mom's probably going to cry on the phone," he said.

Claude Giroux and Jake Voracek scored shootout goals to cap a fantastic Philadelphia Flyers rally in a 4-3 win over the Buffalo Sabres on Tuesday night.

Trailing 3-1, Brayden Schenn and Mark Streit scored power-play goals in the final 3 minutes of regulation to send the game into overtime.

Buffalo's Dmitry Kulikov was whistled for charging when he wiped out Jake Voracek late in the game to start a scrum between the two teams. Schenn quickly followed with a power-play goal with 2:52 left to make it 3-2. Streit scored with 1:51 left in regulation when he knocked in the puck on the fourth rebound past a stunned Anders Nilsson.

Voracek returned after a spell on the bench and his presence gave a boost to the Flyers.

"He's a tough guy. Don't tell him I said that," Giroux said.

Konecny scored early in the third period for the Flyers. Matt Moulson scored two goals for the Sabres.

Moulson scored both goals in a three-goal second period that chased Flyers goalie Michal Neuvirth. Neuvirth allowed three goals on 17 shots and was pulled from net for his second straight start.

The Flyers were listless in their third game in four nights and were soundly booed off the ice at the end of the second.

Those jeers turned to cheers by the time Voracek knocked in Philly's second shootout goal.

Moulson had his first two-goal game since Dec. 11, 2014 against Calgary and has four goals this season. He had eight in 81 games last season.

The Sabres had the last four days off and were clearly sharper early than the Flyers. The Flyers had 10 giveaways through the first two periods and Giroux's boarding penalty early in the second sparked Buffalo to two straight goals.

"We played some bad hockey today," Giroux said. "We know we're a better team than this. Our work ethic kind of got us in the game."

Tyler Ennis opened the scoring 2:06 into the second when the puck appeared to deflect off Streit's right leg.

Battling for the puck behind the net, Giroux plowed his left shoulder into Zemgus Girgensons and sent the centre face-first into the boards. With Giroux in the box, the Sabres capitalized on the man advantage. Moulson's power-play past Neuvirth made it 2-0 and started the boos at the Wells Fargo Center.

Moulson's second power-play goal of the game — and league-high fourth of the season — sent Neuvirth to the bench. Steve Mason, in a battle for the No. 1 spot, replaced Neuvirth and made a nifty stop later in the period to deny Moulson a hat trick.

Mason stopped eight shots and two more in the shootout.

"Guys have a belief that you get one, more are going to come," Mason said. "TK got us going."

The Flyers got a needed lift in the third when Konecny scored his first career goal. The 19-year-old forward was Philadelphia's first-round pick in the 2015 draft and is one of the hopeful cornerstones for the rebuilding franchise.

"He's been buzzing all season long," Giroux said.

The Sabres lamented a big blown opportunity to earn two points.

"It's on us to be better," Sabres captain Brian Gionta said. "We showed we could take over the game and make something happen. We've got to find a way to go into the third and get a win."

Nilsson, who stopped 49 of 50 shots in two preseason games, was solid until the late collapse in his first start of the season. Robin Lehner didn't make the trip after coming down with an illness on Sunday night. He stopped 38 shots.

"I felt like I saw the puck well and I felt like I made some good saves," Nilsson said.

Notes: Flyers D Radko Gudas returned from a six-game suspension for his head shot in a preseason game. ... Sabres F Evander Kane remained sidelined with cracked ribs. "It's more of a pain and discomfort than anything at this point in time. He should be able to start moving here shortly, not crazily, but he should be able to start moving shortly here and kind of go from there," coach Dan Bylsma said.