United's U21s were victorious at Bradford Park Avenue over the weekend.
A double from Otis Khan, the first a rebound after his initial penalty was saved, and a late winner from Joe Cheeseman saw the Blades come from 2-0 down to beat The Avenue 3-2 at a sun drenched Horsfall Stadium on Saturday.
Nathan Hotte and Chib Chilaka put BPA in the driving seat early on, but United's youngsters rallied and in the end were good value for their win as Cheeseman scored from close-range in the final ten minutes.
Meanwhile, United's U18s lost their first game of pre-season, slipping to a 4-0 defeat at Belper Town, managed by former Blade Peter Duffield.
The Nailers, an experienced and well drilled outfit, proved too strong for the Blades, despite a spirited showing from the visitors, particularly in the second-half.