Devon McTavish was credited with an own goal for Houston's first goal, before Geoff Cameron's header in the 70th minute won the game for Dominic Kinnear's side. Dominic Oduro then added a breakaway goal in the 10th minute of stoppage time as United looked for an equalizer.
In the matchup for the wooden spoon, Houston's performance in the second half in front of 13,828 fans at RFK Stadium was enough to earn the three points.
Houston enjoyed the brighter start to the game, creating several chances early on in the match. Andrew Hainault had the first effort on goal, but the Dynamo defender headed Brad Davis' corner over. Corey Ashe had a long range attempt minutes later, but his shot was just over the bar.
Both sides went through the paces for the next 10 minutes of the match, as neither side was able to create any chances, despite some dangerous looking attacks in the final third.
Danny Allsopp had the first shot for United in the 16th minute, but after Santino Quaranta teed up the striker, his shot was wide of the target. Branko Boskovic was then planted a header on target after a free kick from Pablo Hernandez, but Houston 'keeper Pat Onstad was able to make the comfortable save.
Chances began to fall by the wayside again, until Andy Najar broke the deadlock in the 29th minute. Quaranta switched the flank of attack quickly, with his long ball finding Najar on the right. Najar cut behind Hainault and then Adrian Serioux, before firing past Onstad from the middle of the box.
The goal seemed to elevate the play of United, as they began to create even more chances. Quaranta had a dangerous cross that just missed Hernandez at the far post, before Boskovic's volley from the left corner of the box flew into the side netting.
Najar had the final chance of the half, as Houston struggled to clear a cross out of the box. The ball eventually fell to the 17-year-old, who had a clear view of the goal, but his well-hit volley found the side netting as well.
United began the second half much in a similar way to how they finished the first half: creating several early chances. After Allsopp won a corner, Hernandez had a decent chance with a header but sent his effort just over the bar. Allsopp then had a chance himself moments later, but his effort was blocked out for a corner, with teammates lurking in the middle of the box.
The chances continued to come for United, as Quaranta's work down the left wing enable him to send a cross towards the far post for Allsopp. However, the cross was behind Allsopp, and in coming back for the ball, he was unable to direct his header on target.
Allsopp appeared to have a second goal for United in the 60th minute, as he pounced on Onstad's save of Hernandez's shot. However, Allsopp was flagged for offside, and thus, the goal did not stand. Onstad then spilled a cross from Najar in the 62nd minute, allowing Hernandez an opportunity on goal, but Onstad reacted in time to block the shot.
Houston never looked likely to score until they pulled a goal back in the 66th minute. United keeper Troy Perkins flapped at a cross in the box, allowing Brad Davis to try to volley a shot. His effort failed to go on target, but deflected off of Devon McTavish, and rolled in for an own goal.
United nearly hit Houston right back, as Onstad similarly went for a Quaranta cross and missed. Najar arrived late at the far post, but was just unable to redirect the cross on target.
Despite United's dominance of the game for most of the match, it was Houston that found the go-ahead goal in the 70th minute. After a hard challenge from Najar, Davis whipped in a wonderful free kick that was headed in by Geoff Cameron to stun United.
The game went back and forth for the last 20 minutes of the half, with each side getting their chances. The best of the lot fell to Brian Ching, who hit the bar from close range, and Davis, who stung the hands of Perkins on a free kick from the right flank.
United's best chance to find an equalizer came in the 87th minute, as Najar ran onto a pass and broke into the box behind the defense. He tried to bend his shot around Onstad, but Onstad was perfectly positioned to parry away the shot from a tight angle.
Houston then ensured their victory in the 10th minute of stoppage time, as a simple through ball from Ching played Oduro in behind the United defense, and the Houston striker slotted his shot home to seal the victory.
Follow Steven Streff as he chronicles D.C. United's fall from grace in MLS on Twitter @streffsoccer
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