United's U18s strengthened their position in the Professional Development League with an impressive victory over runaway leaders Nottingham Forest at the SteelPhalt Academy.
Kimarni Smith scored the game's decisive goal at Shirecliffe, to further improve the Blades hope of a top two finish, as United inflicted a first defeat since mid October on Jack Lester's Reds.
The Blades, as has so often as been the case this season started brightly and Smith should have scored after a terrific reverse pass by Crofts as early as the sixth minute.
Hallam and the lively Crofts then had opportunities for the hosts, before they duly took a deserved lead in the 20th minute. Crofts carried the ball from deep and his inviting diagonal ball was met by the head of K. SMITH who looped the ball over the Forest goalkeeper and into the net.
Moments later, Hall missed a golden chance to double the lead, heading straight at the keeper from point blank range from Charlesworth's centre.
At the other end, Ramsdale was alert to snuff out the danger on the half hour, before Forest themselves were guilty of missing a clear goalscoring opportunity in the stroke of half-time.
After a dominant opening 45 minutes from the Blades, Forest upped the tempo in the opening exchanges of the second period and applied plenty of pressure on United's defence. That said the home side carried the greater goalscoring threat and could have put the game to bed on several occasions.
Substitute Tyler Smith nearly scored with his first contribution, before Smith and then Hall missed in consecutive attacks when they should have done better as the game entered the final 15 minutes.
A nervy finish followed, with the visitors throwing everything at United, but some resolute defending and a number of brave blocks ensured it was the home side that ran out worthy winners.
Blades: Ramsdale, Charlesworth, Brown, Gilmour, Cummings, Semple, Crofts (Litchfield 66), Slater (Adebowale 89), Hall, Hallam, K. Smith (T. Smith 58)
Unused: Perryman, Ford.