Colin Greening scored the winner at 8:43 of the third period to lift the Ottawa Senators past the Toronto Maple Leafs, 3-2, at Air Canada Centre.
James van Riemsdyk and Dion Phaneuf scored for Toronto in a game tied 1-1 going into the final period. The Leafs almost tied it up in the dying seconds with a wild flurry and goalie James Reimer on the bench.
"Last year, Toronto had us beat most of the games, and it's a rivalry, so it's always nice to beat them," Lehner said.
Reimer, who's battling Jonathan Bernier for the starting job, made 34 saves.
"I was the starter here last year and I had no intention of giving up whether they brought in Bernier or Lundqvist or someone who'd never played an NHL game before," Reimer said.
Said coach Randy Carlyle: "He made big-league stops, played very well."