Tkachuk returned to the lineup after missing a 3-2 overtime win against the Washington Capitals on Saturday with an upper-body injury.
“It felt great," Tkachuk said. "You never like missing games, and nobody hated that more than me.
"(We) really locked it down really well. Guys played hard in front of [Sergei Bobrovsky], but he was unreal again tonight."
Brandon Montour had a goal and two assists for the Panthers (39-16-4), who have won eight of their past nine games and have allowed two or fewer goals in 14 straight (12-2-0). Bobrovsky made 28 saves.
“It is a good win for us against a team with a lot of skill,” Bobrovsky said. “That was a good challenge for us, and we are happy with the result.”
Dylan Cozens and Tage Thompson scored for the Sabres (27-28-4), who had won three straight overall and five in a row on the road. Ukko-Pekka Luukkonen made 34 saves.
“I said [six weeks] ago that we are in a different place right now mentally and with our psyche," Buffalo coach Don Granato said. “Our guys know how to win, have matured through lots of adversity and challenges this year. They are dialed in. I don’t think that’s going to change. They have grown a lot and their appetite is increasing. We’re all watching it happen.’’