After their great start to the season, the Tannadice teenagers fell to a third successive defeat to the Bairns at Stirling University. Throughout it was a keenly contested affair, but the concession of two soft goals proved the visitors' undoing.
After a first half that produced almost nothing by way of goalmouth incident, the deadlock was broken four minutes after the re-start when Falkirk forged in front. Scott Gibb was allowed too much time and space to head in a Chris Mitchell corner from close range.
United retorted ten minutes later when Marco Andreoni's glancing header from a Fraser Milligan cross flew into the top left-hand corner. Both teams had chances to win it with Danny Robertson missing a proverbial sitter for the home side five minutes later, and home keeper Jamie Barclay tipping away Ryan McCord's netbound header with ten minutes left.
But with the game seemingly heading for a draw, substitute Paul Sluddin hit a low 20-yarder that keeper Matthew Curtis couldn't keep out, despite getting a hand to the shot for the winner seven minutes from time.
Team: Curtis, Milligan, Pope, McMechan, McGrath, Mathieson, W Russell, Andreoni, Feeney (J Russell 65), McCord, Paterson. Subs not used: Gray, O'Hara, Allan.