New England Revolution's poor start to the MLS season was compounded as a first-half own goal from defender Jose Goncalves set DC United en route to victory at RFK Stadium.
The key moment came two minutes before the break when the centre-back inadvertently turned the ball beyond Revolution keeper Bobby Shuttleworth.
New England squandered a chance to take the lead themselves on 33 minutes when a through-ball from Teal Bunbury played in Saer Sene, but the forward skied his effort over when in a promising position.
Despite having plenty of opportunities, the visitors were wayward in their attempts to score and registered just one shot on target throughout the game.
They were punished in second-half stoppage time when Fabian Espindola played in Chris Rolfe and the United forward put New England out of their misery with a cool finish.
The result leaves the Revolution firmly at the bottom of the Eastern Conference.
