Rapids 1, D.C. United 0

It was fireworks night Saturday at Invesco Field in Denver but, unfortunately for D.C. United, Colorado owned the only offense that added some sparks to the party.

United failed to muster any sustained offensive firepower while dropping a 1-0 decision to the surging Colorado Rapids.

It was the second loss in the past three Major League Soccer games for United, which also has gone winless (0-4-2) in its past six games in the Mile High City.

D.C. entered the game with a league-best 44 goals and the league's top scoring average of 1.76 goals a game, but managed one shot on goal in the first half.

Colorado (9-11-4) extended its unbeaten streak to five games and climbed to within four points of third-place Los Angeles in the Western Conference.

United entered the match tied with Kansas City for second place in the Eastern Conference but the loss dropped D.C. a point behind the Wizards, who recorded a 2-2 tie on the road against the MetroStars on Saturday.

United rebounded from its first back-to-back losses since April by routing Real Salt Lake 5-1 on Wednesday. But Saturday marked the club's second match in four nights and, including a match in the U.S. Open Cup, its fourth match in eight days.

For the first 45 minutes D.C. appeared sluggish and was unable to recover after Colorado's Terry Cooke gave the Rapids the lead with a goal in the 22nd minute.

Matters grew worse midway through the second half when Jaime Moreno, the league's leading goal scorer, was sent off with a red card after swiping the heels of the Rapids' Hunter Freeman after the whistle.

Per league rules, Moreno will serve a mandatory one-game suspension when United (12-9-5) continues its road swing at FC Dallas on Saturday before returning home for a rematch against the Rapids.

The call displeased United Coach Peter Nowak.

"I think we picked it up and could have had two goals in the first 10 minutes of the second half, but the referees right now are out of hand," Nowak said. "My best players are getting sent off and we have to cover for them in the toughest stretch of the season. That is unacceptable."

Colorado's offense wasn't exactly as explosive as the postgame fireworks display, but Cooke's goal was enough to put away United.

The scoring chance began beyond midfield when Freeman, trapped along the right sideline, sent a long lead pass that found a streaking Jean Philippe Peguero running free behind United's defense along the right wing.

With Peguero open, United goalkeeper Nick Rimando was forced to charge off his line. Peguero promptly slid a pass across the box to Cooke. Despite the efforts of United defenders Brandon Prideaux and Bobby Boswell, Cooke lined a shot into the top right corner of the vacated net for the game's only goal.

It was the second goal of the season for Cooke and the fourth assist of the year for Peguero.

United's offense showed signs of life after halftime, but a one-on-one chance by Christian Gomez sailed wide in the 53rd minute. Moments later, Rapids goalkeeper Joe Cannon saved a point-blank shot by Moreno.

Playing a man down after Moreno's red card, D.C. had one final opportunity to score a tying goal in extra time when Gomez launched a free kick from beyond the top left side of the box, but his liner was caught cleanly by Cannon.

"I think Colorado did nothing," Nowak said. "They had one chance and scored."