Larkin responded to make it 4-2 at 10:16, scoring his 30th of the season on a rebound between Samsonov's pads.
"We missed a breakaway, we missed a penalty shot in the first period, so even though we'd given up a bunch, we probably deserved to have more than we had, and then from there I thought they defended extremely hard," Keefe said. "We didn't generate much of quality tonight at 5-on-5. ... In terms of where I put it, we lost a game on home ice, and that's not acceptable any time."
Larkin shot into an empty net from the corner in the defensive zone with 2:12 remaining for the 5-2 final. It was his second NHL hat trick.
"It's pretty special to do it here, my grandma was here," Larkin said. "She's 88 now and she came to the rink. I got to see her yesterday, and it's always pretty special when you get to do that. That was pretty cool."
NOTES: The Maple Leafs played without forward Mitchell Marner, who Keefe said is dealing with some "bumps and bruises." Defensemen Mark Giordano and Jake McCabe did not play due to rest. ... Kasper, who was selected No. 8 by the Red Wings in the 2022 NHL Draft, had one shot in 14:59 of ice time in his NHL debut.