Matt Hendricks also scored for Washington in the shootout, while Capitals goalie Braden Holtby stopped both of Buffalo's shootout attempts. Mike Green capped a two-goal third-period rally and forced overtime by scoring with 40 seconds left. Troy Brouwer had a goal and assist for Washington, which bounced back from a 3-2 loss to the Islanders on Tuesday to improve to 4-1 in its past five.
Despite earning a point, Buffalo (13-16-6) lost ground to the Capitals (16-17-1), who gained sole possession of 11th place, a point ahead of the Sabres in the tightly contested Eastern Conference standings.
Hendricks scored on the Capitals' first shootout attempt by faking to his right and then going to his left, where he flipped a shot over goalie Jhonas Enroth's pad.
After Holtby got his right pad out to stop Buffalo's Tyler Ennis, Ovechkin sealed the victory by snapping a shot through Enroth's legs.
Brouwer scored on a short-handed 2-on-1 break 2:43 into the third period to cut Buffalo's lead to 3-2.
Green scored with Holtby lifted for an extra attacker. Getting the puck in the middle of the ice just inside the blue line, Green fired a hard shot that sneaked through the crowd and rang the left post. The puck bounced back and then went in off the back of Enroth's outstretched right arm.
With their playoff hopes beginning to dwindle, the Sabres already began looking to the future.
Hours before the game, Buffalo traded veteran defenceman Jordan Leopold to St. Louis in exchange for two draft picks — including a second-rounder. Leopold was in the final year of his contract and Sabres general manager Darcy Regier said he's focusing on improving the team beyond this season.
Both of Leino's goals came from in close, where he was able to convert rebounds.
Enroth was sharp in making his first start in five games.
His best stop came 2:46 into overtime. After getting a piece of a shot from the left point, he dove to left and managed to rob Mike Ribeiro's attempt to convert the rebound.
Then there was Enroth's two saves on bang-bang chances with 2 minutes left in the second period.
He got his left pad out to stop Jason Chimera's shot from the left circle. And Enroth then recovered in time to turn away Green's hard shot from the right point.
NOTES: Buffalo has allowed a league-high six short-handed goals this season. ... Ehrhoff played his 600th career game. ... The Capitals opened a three-game road trip that continues at Philadelphia on Sunday. ... Ovechkin extended his point streak to seven games, in which he has seven goals and 11 points. He has 32 points (20 goals, 12 assists) in 30 career games against Buffalo.