United exit the Carabao Cup at the first round, after losing on penalties.
In an end-to-end tie, in which substitute Billy Sharp cancelled out Jon Toral's first-half opener, City won 5-4 on penalties with debutant Oliver Norwood the only player to miss, going first in the shootout.
Boss Wilder made five changes for the first-round tie, with Norwood making his debut having signed on Monday. Woodburn was also handed his first start, whilst the bench contained Academy graduates Norrington-Davies and Parkhouse.
The Blades made a positive start, with Norwood involved twice, before Marshall cut out Freeman's low cross. In response, Dicko won a corner, from which Stewart fired over on the volley.
And in the 18th minute, it was the visitors who opened the scoring, with a decisive counter attack, TORAL advanced forward before playing in Dicko, he returned the favour with a square ball leaving before the former side-footed home past Moore.
United looked for an instant response, but Burke made a last-ditch tackle to deny Clarke, following Duffy's defence splitting pass. But on 29 minutes, City should have doubled their lead, but Irvine chipped the ball wide when in on goal, after a stepover by Keane.
The game had really opened up following the opening goal and Clarke could have done better from a promising position, before Woodburn stung the palms of Marshall. Duffy then won a free-kick, took it quickly to free Stevens, but Clarke was unable to convert under heavy pressure.
On the stroke of half-time, Woodburn was inches away from connecting with Duffy's deep cross, but unfortunately for United he just failed to get a touch.
At the break, Sharp was introduced, replacing Duffy and within a minute the Blades had a chance, with Lundstram sending an effort over the crossbar after Curry failed to clear. At the other end, Toral fired an effort wide of Moore's far post, despite the ball appearing to go out of play moments before.
City had appeals for a penalty waved away by referee Coy, as Irvine went down under a challenge from Leonard, who headed over Norwood's corner. Back at the other, Fleming got free down the left and cross for Keane, who headed against the post. From a resulting corner, City came even closer, with Egan and Moore keeping the ball out despite numerous efforts to force it into the net.
Chances were coming with regularity and this time, it was the Blades who it the woodwork, with Egan heading against the crossbar at the back post from Norwood's corner. With 15 minutes remaining, United deservedly restored on parity, as SHARP expertly volleyed home from Fleck's inch perfect cross field pass. Moments later, Stevens had the ball in the net, but he was harshly adjudged offside from Norwood's pass.
As the clock ticked past 80, United were firmly on the front foot, but from Basham's pull back Clarke fired over when off balance. United then caught Hull on the break, but Sharp and then Woodburn couldn't get a shot off, in the end Fleck fired over.
Four minutes of added time were signalled, just as Basham thought he'd won it for the Blades, only for Toral to head off the line. United continued to force the issue in a bid to avoid penalties and Stevens was somehow denied by Marshall and the game went to spot-kicks.
United miss (Norwood) - 0-0
Hull score (Toral) - 0-1
United score (Sharp) - 1-1
Hull score (Keane) - 1-2
United score (Woodburn) - 2-2
Hull score (Grosicki) - 2-3
United score (O'Connell) - 3-3
Hull score (Milikovic) - 3-4
United score (Basham) - 4-4
Hull score (Stewart) - 4-5
Hull win 5-4 on penalties
Blades: Moore, Stevens, O'Connell, Lundstram (Fleck 71), Clarke, Woodburn, Egan, Leonard (Basham 60), Norwood, Freeman, Duffy (Sharp 45).
Unused: Henderson, Stearman, Norrington-Davies, Parkhouse.
Hull: Marshall, Burke (Kingsley 36), Stewart, Dicko (Milinkovic 66), Toral, MacDonald, Irvine, Fleming, Keane, Curry, McKenzie (Grosicki 70).
Unused: Long, Kane, Bowen, Sheaf.