Husidic gave Chicago (3-3-4) a 1-0 advantage in the 14th minute with his third marker of the year. On the play, Patrick Nyarko beat a defender and dribbled into the Philadelphia penalty area before finding the Bosnian for an easy goal.
Pappa notched his third goal of the season in the 74th minute, knocking in the rebound of a Justin Mapp shot.
Danny Mwanga got a goal in stoppage time for the Union (2-6-1).
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