The Maple Leafs defeated the Calgary Flames 2-1 in overtime at home Friday.
Jeff Skinner had two goals and an assist, and Tage Thompson had a goal and an assist for the Sabres (6-6-2). Aaron Dell made 21 saves in his Buffalo debut.
"We had time to make a play," Buffalo coach Don Granato said of the deciding goal. "We didn't. You could go into a lot, but just there was time to make a play and we didn't. There was a mistake. It happens."
David Kampf gave the Maple Leafs a 1-0 lead at 2:43 of the first period. He slid a shot in the low slot under Sabres defenseman Robert Hagg, who sprawled on the ice to block it, and through Dell's pads.
Skinner tied it 1-1 at 14:42. Colin Miller's shot from the point hit the end boards to the right of the net and bounced to Skinner, who was fresh off the bench in the left face-off circle.
Ondrej Kase extended his goal streak to three games when he scored from the right circle to give Toronto a 2-1 lead at 7:18 of the second period.
"You can see his confidence continue to grow and grow, in himself and comfortable within our system," said Tavares, the Toronto captain. "He's very crafty with the puck, obviously a really good shot, good release. He's competing extremely hard … and contributing in a big way."
Michael Bunting extended the lead to 3-1 at 8:28 when Jake Muzzin's point shot redirected off a stick to Bunting in the right circle with the net open.
Thompson scored on a one-timer from the top of the right circle to cut it to 3-2 at 17:33.
"I think he's playing great," Skinner said. "You got a guy that big (6-foot-7, 218 pounds) and good with the puck in the middle, he's tough for other teams to defend."