Tom Wilson scored two empty-net goals, and Alex Ovechkin scored in his third straight game for the Capitals (10-8-2). Connor McMichael and John Carlson each had three assists, and Logan Thompson made 26 saves.
Darnell Nurse scored two goals, and Leon Draisaitl had a goal and an assist for the Oilers (9-9-4), who have lost three of four. Connor McDavid had two assists, and Stuart Skinner made 14 saves.
Aliaksei Protas gave the Capitals a 1-0 lead at 2:17 of the first period. Carlson’s shot from the right point appeared to be deflected in front, and Protas knocked the puck into an open net from the far post.
Ovechkin pushed the lead to 2-0 at 6:04 when he deflected Jakob Chychrun’s point shot with Skinner screened. He has three goals during the goal streak.
Nurse pulled the Oilers to within 2-1 at 7:05, scoring on a one-timer from the point off a pass from McDavid.
Leonard increased the lead to 3-1 at 10:34. He gathered a loose puck at the left point, moved into the right face-off circle and scored on a snap shot.
Nurse made it 3-2 at 12:17, taking a Zach Hyman pass from below the goal line and scoring on a wrist shot from above the left circle.
Leonard gave the Capitals a 4-2 lead at 11:49 of the second period when he muscled around Oilers defenseman Evan Bouchard, deked and lifted a backhand shot past Skinner.
David Tomasek cut it to 4-3 at 2:41 of the third period. Andrew Mangianpane got to the puck behind the net and passed in front to Tomasek, who slid a backhand shot past Thomspon.
Anthony Beauvillier scored off a pass from Dylan Strome on a 2-on-1 rush to make it 5-3 at 6:37.
Draisaitl then made it 5-4 on the power play at 7:47, scoring on a one-timer from the right circle off a pass across the slot from McDavid, but Wilson scored empty-net goals at 18:59 and 19:27 for the 7-4 final.