Oshie, who scored the tying goal in Sunday’s wild comeback win over San Jose, tied the game at one as Washington, which has won three straight, scored six unanswered goals after Artem Anisimov gave the Senators a 1-0 lead at 5:40 of the first period.
Ottawa has lost five straight, its second five-game skid of the season.
Ilya Samsonov stopped 26 shots to bring his record to 12-2-1.
Marcus Hogberg replaced him and allowed Ovechkin’s second goal while stopping 10 shots.
Oshie’s tying goal came at 1:19 of the second. Radko Gudas gave Washington a 2-1 lead at 18:32 and Ovechkin’s 25th goal of the season, made it 3-1 at 17:15.
Oshie’s second goal, his third two-goal game of the season, at 41 seconds of the third period, made it 4-1. It was his 18th of the season. Eller’s 11th goal at 2:08 was Washington’s fifth straight goal.
Eller scored the game-winning goal is Sunday’s comeback win.
The second goal was the 684th goal of Ovechkin’s career, tying him with Teemu Selanne for 11th place on the NHL’s all-time goals list. Ovechkin has six multi-goal games this season.
NOTES: The Capitals are 13-8-2 when they alllow the game’s first goal. … Ottawa D Dylan DeMelo returned after missing 10 games with a broken finger. … LW Anthony Duclair returned after missing a game with a foot injury. … Washington D Christian Djoos did not dress due to a lower body injury. … In his third game this season, Senators LW Rudolfs Balcers assisted on Ottawa’s goal, his first point. … C Evgeny Kuznetsov assisted on Gudas’ goal. He has scored in six games_four goals, four assists. … Washington F Tom Wilson and D John Carlson each had two assists.
Senators: Visit Detroit Red Wings on Friday.
Capitals: Visit Philadelphia Flyers on Wednesday.