United were at Creighton for their last home game of the current season, looking to bow out in style with two away fixtures yet to play.
But it wasn't to be as they suffered an early setback at the double as the away team pounced sharply to establish a two-goal cushion.
The visitors had the lead with just six minutes on the clock when they capitalised on a scuffed clearance. And the second goal of the day was again gifted as hesitancy deep inside the home eventually led to a turnover and a clipped finish.
Hetherington was put through after some neat play just before the half hour but the keeper was off his line smartly to charge the shot down.
Chances were few and far between, but a stunning goal from the edge of the area on 55 minutes sealed the points for Salford.
Hardy and Bollado were denied a consolation late in the day, and the Ammies celebrated a deserved victory at the final whistle.
Team - Simons, Potts (Walsh 75), O'Brien, Gordon, Hetherington, Allan, Murray, Swinburn, Park, Hardy, Bollado. Subs - Barry, Bell.
Bookings - Gordon (73)