United's U18s made it back-to-back victories at Shirecliffe with a victory and over Leigh Bromby's Huddersfield Town.
A David Parkhouse penalty was the decisive moment of the contest, but United did it the hard way after Harrison Foulstone was sent off in the second-half.
The opening stages were lively in this all Yorkshire encounter and the Blades were creating the better opportunities, as Oure got the ball out from under his feet and curled just over.
Moments later this was followed by Clare getting on the end of a Potts cross but his effort was saved.
The visitors created a good chance as the game edged towards half-time as a shot came in from just outside the box but Dewhurst got down well to his left and pushed it away to safety.
Shortly after the interval United would be down to 10 men as a missed time last-ditch tackle from Foulstone saw the defender receive his marching orders.
This didn't stop the Blades creativity though as just two minutes later substitute Parkhouse headed just over the bar from a Williams cross.
After the hour another great opportunity presented itself as Parkhouse knocked down a long ball but Oure who fired over.
Oure would be involved again with 15 minutes to go as a ball over the top saw him through but he was upended by a Town defender in the area. PARKHOUSE stepped up and converted the spot-kick to put the Blades ahead.
With a numerical disadvantage, some valiant defending was required as United saw out the game.
Blades: Dewhurst, Cantrill (Neal 45) , Foulstone, Williams, Belehouan, Omar (Gordon 65), Potts, Broadbent, Fleming (Parkhouse 45), Oure, Clare.
Unused: Warhurst, Ompreon.