Justin Williams had two goals and an assist, Marcus Johansson had a goal and two assists and the Capitals closed with six straight goals to beat the struggling Rangers 7-3 on Sunday night at the Garden.
The Rangers led 3-1 after one period, but allowed Washington to rally for its fifth straight win.
The Rangers have lost three in a row and six of eight to fall to 19-12-4 as their slump has gotten out of hand.
J.T. Miller, Chris Kreider and Dan Boyle scored for the Rangers. Henrik Lundqvist made 19 saves before being pulled, and Magnus Hellberg made four saves in his NHL debut.