CHESTER, Pa. — A 10-man Colorado Rapids took the lead and refused to let go despite heavy pressure from the Philadelphia Union to walk out of a sold-out PPL Park on Sunday afternoon with a hard-fought 2-1 win.

Colombian import Jaime Castrillón scored his first goal in MLS to give the Rapids a 1-0 advantage in the second half and rookie Tony Cascio doubled the lead just minutes later.

The Union were unable to capitalize on their chances more than just once, when Lionard Pajoy got on the scoresheet, despite playing most of the second half up a body after Jeff Larentowicz was sent off.

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It was nearly a dream start for manager Peter Nowak & Co., who were opening their home in 2012. Less than 30 seconds into the match, Danny Mwanga got behind the Colorado defense only to be taken down by Drew Moor from behind. Referee Mark Geiger did not whistle for a foul on the challenge, however, and play rolled on.

Making his first start of the season, Mwanga was a focal point of the Union attack early on, combining well with strike partner Pajoy. In the 30th minute, the former Oregon State standout nearly opened the scoring, but was unable to get his foot on the end of a Sheanon Williams chip over the Colorado defense.

In the 41st minute, Keon Daniel – making his first appearance at PPL Park since last August – set Mwanga up with a lofted ball over the top. The subsequent left-footed shot to the far post was stopped by Matt Pickens, with the rebound pushed tantalizingly across the face of goal. Pajoy lunged forward to finish the opportunity, but Moor swept away the danger.

The teams went into the locker rooms at halftime tied 0-0, and though the Union continued to control the run of play after the break, it was Colorado who struck first.

In the 56th minute, Omar Cummings got to the endline and played in a cross that slipped through the hands of Philly 'keeper Zac MacMath but didn't escape Castrillón, who tapped in the loose ball at the back post.

The complexion of the match changed drastically for the visitors just moments later, though, as Larentowicz was sent off for his second yellow card.

Despite the subsequent Union onslaught and the man disadvantage, the Rapids managed to double their lead in the 62nd minute, when Cascio got in behind Chris Albright on the wing, moved in on goal, and fired under the leg of MacMath and into the net.

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Looking to cut into the lead, Nowak brought on Roger Torres, and the move paid immediate dividends. In the 67th minute, Torres gathered a cleared corner kick and whipped a curling cross into the penalty area. Pajoy met the service just outside the six-yard box and powered a diving header under the arms of Rapids netminder Matt Pickens to halve the deficit.

The Union came within inches of tying the score in the 71st minute. With a few quick cuts, Pajoy eluded a couple of challenges inside the box before putting a pass across the box. Michael Farfan redirected the close-range delivery, but his looping attempt on goal bounced off the crossbar before being cleared away.

Philadelphia continued to push for an equalizer, with Josué Martinez entering the match in the 79th minute. An aggressive aerial challenge from the former Saprissa striker set up Pajoy at the top of the box, but the Colombian’s open look went high and wide.

Despite their best efforts, the Union ultimately could not find a second goal, with Colorado hanging on for the 2-1 victory.

The loss was the Union’s first in a home opener, giving the team an 0-2-0 record for the first time to start a season. The club will look to rebound next Saturday when they travel to take on the Chicago Fire at Toyota Park.

For the Rapids, the win moves them to a perfect 2-0-0 to start the season. They will head to New York next to face the Red Bulls next Sunday in a match that will be broadcast on ESPN (4 pm ET)

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