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Originally, four of the ten MLS teams entered the tournament. Five ended up participating, as D.C. United replaced the Los Angeles Galaxy (due to the Galaxy's congested schedule), and the Colorado Rapids replaced the Colorado Foxes (when the team could not reschedule its third-round match against Kansas City). The A-League Rochester side beat two MLS teams en route to the final before falling to already-crowned MLS Cup champion United.
Note: The Colorado Rapids replaced the Colorado Foxes when the team could not reschedule its Quarterfinal match after player availability conflicts due to CONCACAF World Cup Qualifying.