Chris Morgan's youngsters came off the back of two consecutive defeats to secure a deserved victory in this encounter against Huddersfield, who are already the U21s professional development league winners for the region.
Blades coach Morgan explains: "Last week I was quite critical of the lads, they didn't do the ugly stuff associated with getting a result but it appears that they have taken the chat we had on board.
"Huddersfield have a FA Youth Cup game so they had no scholars whatsoever in their side, which was mainly made up of professionals. We, on the other hand, have made a conscious decision to attempt to give as many young players as much exposure to the U21s as possible, which makes this result all the more sweet.
"Everyone contributed but I must give a mention to the two young central defenders, Julian Banton and Ioan Evans, who did a great job against Harry Bunn and Jon Stead, who, of course, played with us in the Premiership year."
The Blades took the lead on five minutes but Huddersfield levelled through Stead on 19 minutes.
United, however, secured the points with a penalty on 66 minutes. Whitehouse converted from 12 yards after McFadzean was fouled as he attempted to get on the end of a De Girolamo lob.
The victory gives the Blades a boost ahead of next week's U21s fixture - a clash with Sheffield Wednesday at Shirecliffe.
Blades: Long, Paling, Johns, Dimaio (Reed 80), Banton, Evans, Khan, Whitehouse, Eyre (Calvert-Lewin 69), De Girolamo, McFadzean (Whiteman 80).
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