Fagundez got his 13th goal of the season after receiving a low cross from Andy Dorman.
A.J. Soares and Chris Tierney also scored for the Revs (13-11-9) joined the Top 5 in the Eastern Conference with one game to play.
Dominic Oduro and Aaron Schoenfeld scored for the Crew (12-16-5), who were officially eliminated with the loss.
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