COMMERCE CITY, Colo. (AP) -- Jack McInerney scored in the 79th minute as the Philadelphia Union defeated the Colorado Rapids 2-1 on Sunday.
Amobi Okugo added a goal for Philadelphia (1-1). The third-year MLS expansion team was 0-3-2 in the first five meeting with the Rapids.
Longtime Rapids forward Conor Casey did not make the trip with Philadelphia because of an injured right hamstring.
Antoine Hoppenot found McInerney in stride along the right side. Hoppenot beat goalkeeper Matt Pickens past the left hand to break a 1-1 tie.
Severe weather conditions forced the postponement of the game originally scheduled for Saturday.
Jamie Smith scored in the 69th minute for Colorado (0-2). The Rapids had been unbeaten (6-0-3) in their previous nine home openers.
Colorado played without midfielder Edson Buddle, held out with fluid buildup in his right knee.
Philadelphia had a huge disadvantage in possession time in the first half and rarely had the ball in the scoring zone, but led 1-0 at the break. Aside from the goal, the Union had one serious threat, a free kick by Keon Daniel in the 23rd minute that curled around the right post.
The Rapids had their chances. Forward Deshorn Brown missed the right post off a corner kick in the 10th minute and had a shot from deep inside the Philly zone blocked by Union defenders in the 26th minute.
In the 19th minute, Kevin Harbottle found Hendry Thomas in front of the crease, but goalkeeper Zac MacMath blocked the shot and swatted it out of harm's way.
The Union got their first goal off a corner kick by Sebastian Le Toux. Okugo outmuscled Colorado defender Marvell Wynne for the ball and put the ball into an untended part of the net.
Colorado lost injury-plagued midfielder Pablo Mastroeni to a left hamstring injury in the seventh minute.
The Rapids had two chances get away early in the second half. Brown caught all turf on an empty net opportunity, and a second chance from 20 yards sailed past the left post in the first seven minutes.
Michael Farfan broke free along the right sideline in the 57th minute, but goalkeeper Matt Pickens came well out of his crease to keep it a one goal lead.
The Union had a goal by Brian Carroll waved off by an offside in the 59th minute.
Smith scored on a long pass by Brown in the 69th minute. Smith got behind the defense and sent a left-footed shot past MacMath.
Philadelphia responded with McInerney's winner in the 79th minute.