BUFFALO -- The Florida Panthers missed an opportunity to gain ground in the Stanley Cup Playoff race with a 4-2 loss to the Buffalo Sabres at KeyBank Center on Monday.
Florida (33-31-11) is seven points behind the Boston Bruins for the second wild card in the Eastern Conference with seven games remaining.
"We didn't play the way we're supposed to," Panthers coach Tom Rowe said. "We weren't prepared mentally or physically, and that's what happens when you come into a building like this and they're ready and we weren't. That's what happens."
WATCH: All Panthers vs. Sabres highlights
The Sabres (32-32-12) have won four of their past five games.
Ryan O'Reilly gave the Sabres a 1-0 lead when he put a rebound of Jack Eichel's shot past James Reimer for a power-play goal at 3:21 of the first period.
Zach Bogosian made it 2-0 at 14:06 of the first period when he put a rebound of his own shot that went off the post and past Reimer for his second goal.
Video: FLA@BUF: O'Reilly goes top-shelf to bury the rebound
Brian Gionta made it 3-0 with a power-play goal at 1:25 of the second period when he shot the puck from the side of the net off Jason Demers and past Reimer.
Gionta played in his 1,000th NHL career game.
"It was a special night for Brian and his family and one he richly deserved, but when he scored the goal, I think half our benched jumped up like it was a playoff goal," Sabres coach Dan Bylsma said. "I think everyone was pleased to see him get the reward and in a fitting way. It was kind of a goal scorer's goal around the net."
Jonathan Marchessault made it 3-1 with a power-play goal at 10:19 of the second period. Marchessault received a pass from Jonathan Huberdeau in the slot and took a shot that beat Robin Lehner for his 29th goal of the season and his sixth in the past three games.
Marcus Foligno made it 4-1 at 15:08 of the second period when he took a shot from near the boards that beat Reimer for his 13th goal.
Reimer was replaced by Reto Berra after Foligno's goal. Reimer allowed four goals on 22 shots; Berra made 10 saves.
Video: FLA@BUF: Bogosian pokes the loose puck past Reimer
"Any time you don't win at this stage of the season it's a tough one to swallow and there's no accepting for that," Panthers defenseman Keith Yandle said.
Huberdeau scored 1:02 later when he faked a shot and slipped the puck past Lehner to make it 4-2.
Lehner made 30 saves.
Goal of the game
Huberdeau pulled back as though he was going to take a snap shot, which was enough to get Lehner out of position for a deke.
Video: FLA@BUF: Huberdeau nets crafty goal off a turnover
Save of the game
Lehner turned aside Reilly Smith's penalty shot at 5:23 of the third period. "I tried to play it a little as a breakaway. He came with a lot of speed too. It's a little bit easier for me. I'm fortunate, I have a hard time handling when it comes low," Lehner said.
Video: FLA@BUF: Lehner flashes glove on Smith's penalty shot
Highlight of the game
Gionta's bank shot proved to be the game-winner. "I didn't know at first whether it went off [Matt Moulson] or the [defenseman], just a lucky bounce I guess on this night," Gionta said.
Video: FLA@BUF: Gionta beats Reimer after slick deke
Unsung performance of the game
Sabres defenseman Josh Gorges was plus-2 with four hits and played 3:46 of his 16:34 on the penalty kill.
They said it
"I'm a guy that likes to stay behind the scenes; I don't like to be out in front of it. So for tonight to be the focus early on for the ceremony and whatnot, I'm just a humble kid from Western New York and I just try to take it all in." -- Sabres captain Brian Gionta on his 1,000th NHL game
"I don't think we were as good as we were last game. I think we knew coming into this game, even though we scored seven last game, we knew we had to be just as good defensively. Speaking for myself, I know I wasn't as good as I needed to be and it's … I'll have to be better tomorrow." -- Panthers defenseman Keith Yandle
Need to know
Marchessault leads the Panthers with 29 goals. … Eichel had two assists and has 55 points (23 goals, 32 assists) in 55 games. … The Sabres are 8-1-1 in their past 10 games against Atlantic Division teams, their best stretch against divisional opponents since 2010-2011.
Panthers: At the Toronto Maple Leafs on Tuesday (7:30 p.m. ET; TSN4, FS-F, NHL.TV)
Sabres: At the Columbus Blue Jackets on Tuesday (7 p.m. ET; FS-O, MSG-B, NHL.TV)
Video: Sabres double up Panthers, 4-2, in Buffalo