Mexican international striker Guillermo Franco earned red for a studs-first challenge on Brian Carroll in the Fire's 3-1 loss to Philly.
Just seven minutes in the Union opened the scoring. Danny Cruz split the high Fire backline with an outside-of-the-boot pass. Jack McInerney tucked home the simple left-footed finish.
McInerney turned provider for the second, midway through the second half. The 20-year-old headed down a lofted ball. Gabriel Gomez ran onto it and smashed his shot into the far upper corner.
Dominic Oduro cut the deficit in half with a bobbling low shot, but any hopes of a Fire comeback were extinguished when substitute Guillermo Franco was ejected in the 79th minute.
With five minutes remaining, Antoine Hoppenot rubbed in the result by finishing Michael Farfan's long run and low cross with an unmarked backheel.
Former Philly manager Peter Nowak was honored, along with Cuauhtemoc Blanco and Chris Armas, at halftime as part of the Fire's 15th anniversary celebration.
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