United's Under 23s fell to defeat in the Sheffield derby under the lights at Bramall Lane as goals from Rolando Aarons and Conor Grant sealed victory for the visitors.
In truth, United never got going despite several first team players, including Paul Coutts, making the starting line-up but Wednesday themselves put out a strong line-up for the evening.
The opening half an hour saw very few chances and it somewhat set the tone for the rest of the night, goalkeeper Simon Moore pushing away a curling effort about the only talking point of the opening exchanges.
But Wednesday did take the lead just shy of the half hour mark when a quick break up the pitch led to Aarons firing home a powerful effort with his left foot which was too hot for Moore to handle.
The next 15 minutes saw United have their most consistent spell of the game but without the chances to match.
Harry Sheppeard and Harry Boyes both provided teasing crosses from the full-back positions but the ball wouldn't drop in the right positions as United went in 1-0 at the break.
Kean Bryan came closest to an equaliser immediately after the game resumed when his looping header was well saved but the final blow came just minutes later and a defensive mix-up allowed Grant to steal the ball and finish into the bottom corner.
It left the Blades with a mountain to climb and they were never able to create the chances needed to get back into the game.
Bryan saw another header deflected behind before another corner led to substitute Simeon Oure firing just over, but set-pieces were as close as United came on an ultimately frustrating evening at Bramall Lane.
Blades: Moore, Ferguson, Bryan, Broadbent, Wright, York (Neal 86), Sheppeard, Coutts, Washington (Oure 46), Greaves, Boyes.
Unused: Dewhurst, Bennett, Belehouan.