WASHINGTON -- Brian Mullan and Brian Ching scored goals as the Houston Dynamo beat D.C. United 2-0 Wednesday in a match that was delayed nearly three hours by a power outage and thunderstorms.

It was the first MLS road win for Houston (5-4-8) since a 2-1 victory at Chicago on May 17.

United (7-8-1) had a four-game winning streak end.

Heavy rains began early in the second half. The RFK Stadium lights flickered and went out and the match was halted in the 54th minute. After a delay of 2:54 the game started again around 11:40 p.m. The game ended at 12:20 a.m. ET in a light drizzle.

The game was originally scheduled for June 4 but was called off after 16 minutes of play due to a thunderstorm. The game was rescheduled for Tuesday, but a power outage in some parts of Washington pushed the game back a day until Wednesday.

Mullan scored his first goal of the season in the 20th minute and Ching scored a team-high seventh goal of the year late in the second half.

Houston goalie Pat Onstad made a nice save with about 20 minutes left on a shot by Clyde Simms.

United had not lost since a 1-0 setback at Toronto FC on May 21. United played without defender Gonzalo Peralta and midfielder Marcelo Gallardo, both of whom have groin strains.

Houston beat United 3-1 on Saturday in Washington in a SuperLiga match. The Dynamo had 12 shots in the first half Wednesday while United had just one.