United's Under 18s lost out to Leeds in a five-goal thriller at Thorp Arch but it wasn't for the want of trying after being reduced to ten men inside 20 minutes.
Second half goals from Sam Ackroyd and a Reon Potts penalty was the least the Blades deserved for their efforts after Frankie Maguire had been showed a straight red card early in the game.
It was a fraught and frantic encounter and despite missing several key players it was United who started on the front foot, playing good possession football without troubling the Leeds goal.
But the game turned on a high challenge from Maguire on Theo Hudson in the centre of the field. While there was no malice from the youngster, the referee was left with little choice but to bring out the red card.
After a delay of eight minutes while Hudson was treated and stretchered off the pitch, Leeds took advantage immediately after the restart, finding space to allow Henri Kumwenda to slot home.
The Blades tried to gather themselves and readjust but the hosts had the better of the rest of the first half in terms of chances.
Sam Kelly made two good saves before a cross from the left by Josh Shergill evaded him and found the corner of the net just before the break.
The two-goal margin with a man advantage should have been impossible for the Blades to come back from but the second half performance was one of the best the team has put in all season and they came out flying from the off.
Less than three minutes had passed when Potts's cross found Ackroyd, the striker bundling the ball home at the second time of asking after seeing his initial effort saved.
Zak Brunt forced another save as the Blades continued to pile on the pressure despite a man deficit, but it looked like Leeds had put the game beyond doubt with 20 minutes to go when Niall Huggins smashed home a cross from the left.
United were furious as it looked like the ball had gone out for a throw-in in the build-up, teamed with potential offsides on both first half goals it had been a day where not a lot had gone United's way.
But it did go their way minutes later when Tom Williams was fouled inside the box, the resulting penalty tucked home calmly by Potts to bring the gap back to one.
After a valiant performance, the Blades threw everything at it late on as even Sam Kelly came up for a last-minute free-kick, but the only major chance fell to Tristan Skerritt who fired inches wide from the edge of the box.
Blades: S. Kelly, J. Kelly, Foulstone, Williams (Ompreon 82), Skerritt, Gomis, Gaxha (Stainrod 77), Maguire, Ackroyd (Hackford 71), Potts, Brunt.
Unused: Chapman, Anderson.