United's U18s saw their three match winning run in the FA Premier Academy League ended by Middlesbrough at Rockliffe Park at the weekend.
Jake Fowler scored the only goal of the game just before the half hour to settle a keenly contested fixture, which was played in an excellent spirit by both teams.
Jordan Jones was a constant threat to the Blades, but he found George Willis at the top of his game. The England stopper denied Jones three times in total, with the most notable coming midway through the second-half.
For the Blades, Owen Heather drew a fine save from James Montgomery in the Boro goal, whilst the woodwork came to the hosts rescue when Adam Hinchliffe struck the bar with a dipping shot from 25 yards.
United continued to knock at the door, Joe Ironside should have scored when he headed straight at Montgomery, before he shot wide from the edge of the box. Moments later Aaron Barry surged forward, only to see his angled drive go just wide after carrying the ball the length of the field.
Willis kept the Blades in the game as they chased that elusive equaliser, firstly denying Andre Bennett, before producing an even better reflex stop to keep out Zak Boagey's effort.
John Pemberton was delighted with the application and attitude of his players and reserved praise for how both teams for their football and discipline:
"It was a really good game played by two excellent footballing sides who keep the ball really well.
"We had our chances to get a draw which was probably a fair result, but at the other end George Willis has kept us in the game with some excellent saves.
"It is disappointing that we effectively lost the game through a momentary loss of concentration but there are plenty of positives for us to take from the performance."
Blades: Willis, Hinchliffe, T. Williams (Anderson 74), Pemberton, J. Williams, Barry, Deakin, Whitehouse, Ironside, Heather, McFadzean (Smith 56).
Unused: Salt.