Juuse Saros made 17 saves and Matt Duchene scored for the Predators (24-12-2), whose winning streak ended at five games. The Predators had gone 12-1-1 in their previous 14 games.
"Definitely not our best game," Predators captain Roman Josi said. "I think we came out kind of flat, didn't have a good first period. They were just faster. They were quicker on pucks and outbattled us. I thought we played a little better in the second, but just overall, we didn't have enough pressure. We didn't have enough zone time in their end."
Dell had been recalled Wednesday from Rochester of the American Hockey League after goalies Ukko-Pekka Luukkonen (lower body) and Malcolm Subban (upper body) were injured in a 6-1 loss to the Tampa Bay Lightning on Tuesday. Dustin Tokarski is in COVID-19 protocol.
It was Dell's first NHL win since April 8, 2021 with the New Jersey Devils against Buffalo.
"He has struggled with us this year, Aaron," Granato said. "I was able to go see him in Rochester last week. Last Friday, he looked like a different guy. He's worked to be that. It was great to see him win tonight."
Mark Jankowski scored at 14:30 of the first period to make it 1-0 Sabres. It was his first goal with Buffalo. Mark Pysyk's shot from the point deflected off Jankowski on the way to Saros. When Nashville defenseman Matt Benning tried to clear the puck from the crease, it bounced off Saros' pads and in.
Duchene tied it 1-1 at 13:12 of the second period, scoring his third power play goal in two games. He slapped a bouncing puck in the slot, after Dell stopped a shot from Josi. Duchene extended his point streak to four games (four goals, one assist).
"Buffalo was the better team," Predators coach John Hynes said. "They were faster, they were harder, and they were more competitive. They executed with the puck better. They were the better team tonight."