BUFFALO -- The Tampa Bay Lightning had their lead over the Boston Bruins in the Atlantic Division cut to one point after a 5-3 loss to the Buffalo Sabres at KeyBank Center on Tuesday.
Sam Reinhart scored twice, and Ryan O'Reilly had a goal and two assists to help the Sabres (17-30-10) to their third win in their past four games (3-1-0).
The Lightning (38-16-3), who lost 4-3 at the Toronto Maple Leafs on Monday, have lost three of five games (2-3-0). Boston defeated the Calgary Flames 5-2 at home Tuesday.
[WATCH: All Lightning vs. Sabres highlights]
"We lost the hockey game," Lightning coach Jon Cooper said. "We lost two in a row within 24 hours. You're right, we're not used to it, but if you keep playing this way, things like this are going to happen."
O'Reilly's 18th goal of the season gave the Sabres a 4-2 lead at 3:41 of the third period when he put a rebound of a Kyle Okposo shot past Louis Domingue on the power play. O'Reilly's goal was the game-winner after Lightning forward Ryan Callahan made it 4-3 at 11:36.
O'Reilly also set up Reinhart's power-play goal at 1:16 of the second period and has 13 points (seven goals, six assists) in his past 11 games. He assisted on Reinhart's empty-net goal with eight seconds remaining in the third that made it 5-3.
Video: TBL@BUF: Reinhart buries PPG on O'Reilly's rebound
"He does it all," Reinhart said of O'Reilly. "Playing with him, I've been with him and [Jack Eichel] a lot lately and they've both been unbelievable in the face-off circle and that makes it so much easier as a winger; that makes it so much easier on everyone when you start with the puck. It's just little things just like that and the two-way game he has is something everyone can watch and learn from."
The Sabres went 2 for 3 on the power play.
"Our (penalty) kill gives up one there in the third and it definitely hurts us," Callahan said. "At the same time, we score in a one-goal game and we don't have an emotional push after that. No real sustained pressure or opportunities, which is disappointing."
Scott Wilson and Nicholas Baptiste scored, and Chad Johnson made 26 saves for the Sabres.
Baptiste gave the Sabres a 1-0 lead at 6:25 of the first period when he received a pass from Zemgus Girgensons and put a shot past Domingue for his second goal.
Yanni Gourde made it 1-1 at 13:23 of the first period when he redirected a pass from Nikita Kucherov past Johnson for his 22nd goal.
Video: TBL@BUF: Gourde redirects Kucherov's feed for PPG
Gourde has 10 points (five goals, five assists) during a seven-game point streak.
After Reinhart made it 2-1, Lightning forward Vladislav Namestnikov made it 2-2 at 13:19 of the second when he picked up a loose puck after a turnover and bounced the puck off Johnson for his 19th goal.
Wilson gave the Sabres a 3-2 lead with 4:13 remaining in the second when he tipped a shot by Casey Nelson past Domingue for his fourth goal.
"The first thing I said was 'Way to be patient,' because I was kind of coming a little bit late," Wilson said. "I knew [Nelson] wasn't going to shoot it away, had a little bit of a fake, and luckily enough I was able to get a piece of it and beat the goalie."
Goal of the game
Wilson's goal at 15:47 of the second period.
Video: TBL@BUF: Wilson tips in Nelson's shot while airborne
Save of the game
Johnson's save against Brayden Point at 7:23 of the second period.
Video: TBL@BUF: Johnson stones Callahan, Point with pad
Highlight of the game
O'Reilly's power-play goal at 3:41 of the third period.
Video: TBL@BUF: O'Reilly shovels home PPG from behind net
They said it
"We're an honest group in here. We've said that all year. We're honest with each other. We're honest with our effort, our play. So we'll look at both these games and correct the things we need to correct and move forward. There's no real time to rest. We've got one day here and we're right back at it (Thursday) against a Detroit (Red Wings) team that always seems to get the best out of us. It's always an emotional game, so I think that's going to help us." -- Lightning forward Ryan Callahan on losing two straight games
"Those kinds of moments, the key moments, whether it's guys blocking shots or killing a 5-on-3, it's that momentum, it's that energy we're gaining from the fans and we're giving them something to cheer about on our side, so when we do kill it, we turn around and use it as momentum for us. That's what we did. Guys were really dialed in blocking shots." -- Sabres goalie Chad Johnson on Buffalo killing a second-period power play when the Lightning had a 5-on-3 advantage for 1:53
Need to know
Kucherov (one assist) has eight points (three goals, five assists) in his past six games. … Okposo (one assist) has 15 points (three goals, 12 assists) in his past 15 games.
Lightning: Host the Detroit Red Wings on Thursday (7:30 p.m. ET; SUN, FS-D, NHL.TV)
Sabres: At the Ottawa Senators on Thursday (7:30 p.m. ET; RDS2, TSN5, MSG-B, NHL.TV)
Video: O'Reilly, Reinhart lead Sabres past Lightning, 5-3