Seth Kuhn scored in the 22nd minute on Wednesday to put the U19s up 1-0 on the Portland Timbers, but a 68th minute strike from Wilterlynd Inalien gave Portland a share of the spoils and also of the top spot in the group.
Both teams sit on four points with one game remaining, but the Union do have a two-goal advantage in goal differential. Only the top finisher in the group will advance to the quarterfinals.
The U17 team, meanwhile, has a steeper hill to climb after a 2-0 loss to open group play on Tuesday against Orlando City.
Nico Diaz was the assassin for Orlando, scoring in the 48th and 65th minutes. The U17s play Barca Academy tonight in a must-win scenario.