John Carlson had a goal and two assists for the Capitals (19-11-4), who had lost three straight (0-2-1). Justin Sourdif had two assists.
Dennis Hildeby made 23 saves for the Maple Leafs (15-13-5), who have lost three of four (1-2-1).
Aliaksei Protas gave the Capitals a 1-0 lead at 13:53 of the first period. Sourdif controlled a loose puck in front, skated around Hildeby’s outstretched pad and passed in front to Protas for the tip-in.
Chychrun made it 2-0 at 16:16. Connor McMichael’s shot from the left point was tipped by Ethen Frank, bounced off the end boards and out to Chychrun, who scored on a snap shot from just below the right circle.
Chychrun increased the lead to 3-0 at 4:02 of the third period when he skated down into the left circle and scored far side with a wrist shot from the face-off dot.
Carlson made it 4-0 at 8:57 when he got to a loose puck along the right boards and sent a high slap shot past Hildeby.