With the score tied 2-2, Kevin Ellis, making his MLS debut, lofted a ball into the penalty area, where it deflected to Claudio Bieler and then onto a wide-open Kamara, who scored from in close.
Kamara also scored in the 34th minute and Bieler added a tally in the 50th for SKC (7-5-5), which registered it first win in five games.
Jairo Arrieta and Dominic Odura each scored for the Crew (5-7-5), who fell for the third time in four contests.
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