DC United missed the chance to extend their lead at the top of the Eastern Conference as Portland Timbers clinched a 1-0 victory at Providence Park on Wednesday evening.
Portland were ahead inside five minutes when Gaston Fernandez won possession out wide before delivering a low cross to allow Maximiliano Urruti to tap home from close range.
The hosts applied pressure for long spells of the first half, but they missed a good chance to double the lead when Liam Ridgewell headed straight at Bill Hamid.
Ridgewell's aerial ability caused a number of problems for the visiting defence, with Hamid forced to make an impressive stop to keep out the defender before the break.
Portland threatened to extend their advantage just after the break when Diego Chara won the ball on the edge of the box, but he could only send his shot just over the crossbar.
Despite offering very little attacking threat, DC remained in the game heading into the closing stages, thanks largely to Hamid, who closed the angle on Dairon Asprilla to make another save and the winger was denied once again a few moments later.
However, the visitors were unable to hit back late on as Portland comfortably secured the win.
Callum Mulvihill
