By Harvey Hoffman
Sergio Santos raced behind his man to create a breakaway, and then while still charging toward the goal he chipped a delicate finish over charging goalkeeper Tim Melia.
His second goal came 13 minutes later through more conventional attacking play.
Brenden Aaronson took a pass from Alejandro Bedoya and spotted Santos sprinting into the left side of the penalty area with a slick diagonal pass.
Santos finished low and hard past Melia to put the Union up three.