United's U23s fell short in the Steel City derby on Tuesday night with second half goals from Lucas Joao and Almen Abdi cancelling out Tyler Smith's opener.
The result at Hillsborough sees a youthful Blades side remain second in the Professional Development League 2 table.
The first opportunity of the night fell the Owls way as Abdi took aim from 20 yards and fired just over Warhurst's goal on 15 minutes. Wednesday would continue to try and find an opener with Joao firing just wide of a post after a smart turn in the area.
Just a couple of minutes later the Blades came close to breaking the deadlock with an outstretched Hallam poking just wide from Smith's cross following skilful play on the right.
Warhurst was forced into a fine save to his left after Matias fired from just inside the box following Joao having an initial effort blocked.
The deadlock would be broken just before half-time as United's SMITH passed into the bottom corner after Doherty broke through the Owls defence and squared it to his teammate to give the Blades the lead.
The lead was almost doubled as the ball fell to Smith with his back to goal from point-blank range but he failed to make sufficient contact with his header and the scores would be levelled on 66 minutes as Penney's cross found JOAO, who stabbed home from six yards.
Penney almost gave Wednesday the lead with a fierce strike stinging the palms of Warhurst from 25 yards resulting in a corner. The experience in the Owls team, though, paid off with 15 minutes remaining as ABDI caught a falling ball on the volley, which crept passed Warhurst to give Wednesday the lead.
United would push for an equaliser for the remainder of the game but couldn't quite create a clear cut chance.
Blades: Warhurst, Broadbent (Cutts 80), Ferguson, Gilmour, Graham, Cantrill, Doherty, Slater (Portman 68), Smith, Greaves, Hallam (Moore 62).
Unused: Belehouan, Potts.