United's U18s slipped to their first defeat of the season on Saturday, at the hands of Crewe Alexandra at the Redtooth Academy.
The visitors scored a goal in each half to end the Blades unbeaten start to the season.
The home side started the game brightly and had two good openings in first 10 minutes, but neither Coustrain or Dimaio could apply the finishing touch. The Alex scored with their first meaningful in the 12th minute.
The first-half continued to ebb and flow, Crewe went close from a corner, whilst at the other end Heh and Cockerline had chances to restore parity and Reed volleyed over from the edge of the area.
United again started the game on the front foot after the break, but fell further behind just before the hour mark, after Chesseman gave away a penalty that was duly converted.
Wright, Lewin and Taylor were all introduced from the bench and the Blades deserved a goal for their endeavours, following a strong finish, but it wasn't to be. Wright and Cockerline came closest to a consolation in injury-time.
On the defeat, Coach Travis Binnion commented: "The scoreline wasn't a true reflection of the game, but it should be a really good learning curve for the lads against another top Academy outfit.
"We moved the ball well and it was pleasing to see 11 of the lads back in youth team having being involved with the U21s at Hillsborough 24 hours previous.
"That supports the belief we have in this group of players."
Blades: Owen, Paling, Ptak, Reed, Cheeseman, Scarisbrick, Heh (Wright, 60), Whiteman, Cockerline, Dimaio (Lewin, 60), Coustrain (Taylor, 60).