Barklage's deflected header off a corner kick at first appeared to have broken the goal line, but Hamid pulled off a leaping save.
Video replays proved inconclusive, enabling D.C. United (1-1-1) to earn a point with the draw.
Hamid also made a big stops on Tim Cahill and Thierry Henry en route to the tie.
The Red Bulls (0-1-2) remained winless despite outshooting their opponents 24-4.
Swim Week Miami Beach 2014 [PHOTOS]