Toronto's loss puts them eight points behind the Sabres, Bruins, and Canadiens for the final wild-card spot in the East.
The Toronto Maple Leafs might've had the first punch, but the Buffalo Sabres countered and ultimately won the big Atlantic Division matchup 7-4.
All on the 50th anniversary of Darryl Sittler's 10-point night.
Matthew Knies got Toronto started seven minutes into the first period. Jake McCabe's shot bounced off Matias Maccelli, and Knies shovelled it in for his 13th goal of the season and first marker in 11 games.
After a quick goal from Rasmus Dahlin, banking the puck off Morgan Rielly and past Joseph Woll, Auston Matthews scored off a Max Domi rebound.
It was Matthews' team-leading 26th goal of the season, putting Toronto up 2-1.
Not even five minutes later, Josh Doan's pass in front ricocheted off Troy Stecher's stick and into the net on the power play, tying the game at two.
Then, late in the opening frame after a failed clear by Domi, Tage Thompson fired a puck through traffic, beating Woll under the blocker.
That sent Toronto to the dressing room down by a goal.
The Maple Leafs didn't come out so hot in the middle frame. They didn't register more than two shots in the first 11 minutes. But they found some life after Bobby McMann ripped a wrister past Colten Ellis.
Matthews drew three Sabres plays around him and fanned on his shot, which McMann then picked up and fired off the post and into the net. McMann's 17th goal of the year tied the game, and it should've awoken the Maple Leafs.
And maybe it did. However, Buffalo wasn't ready for the round to end quite yet.
Midway through a change (Scott Laughton coming on for Matthews), McMann was caught in his own end chasing around Dahlin. Buffalo defenseman Mattias Samuelsson threw a puck at the net, and McMann couldn't fully tie up Dahlin, who got a stick on the shot and scored the go-ahead goal.
That's where Buffalo wobbled Toronto.
Sixteen seconds into the third period, Thompson got around Jake McCabe and fed Alex Tuch. The forward couldn't control the puck at first, but once he did, he fired it over a sprawling Woll to put the Sabres up even more.
And they didn't let up.
With just over eight minutes left in the game, Jack Quinn walked in and wired a shot by Woll, extending the Sabres' lead to three.
And that's when the booes rained down inside Scotiabank Arena.
Despite a late goal from Domi, who tallied his eighth of the season to make it 6-4, Dahlin scored an empty-netter, completing the hat trick. Toronto fell to the Sabres, losing their fifth straight game and inching further out of a playoff spot.
Where do they go from here?