United's penalty shoot-out woes continue - this time suffering a Johnstone's Paint Trophy Northern Area quarter-final defeat at Coventry City.
Only young striker Joe Ironside scored in the 4-1 shoot-out defeat.
The game had finished 1-1 - the same as the league encounter between the sides in August. On this occasion, David McAllister cancelled out an own goal from Harry Maguire, both goals coming in the second half.
Homegrown McFadzean made his first Blades start, the 18-year-old was one of four changes made by boss Wilson. Also included from the start were Cresswell, Cofie and Williams - Collins, Blackman, Porter and Miller all sat out. Another Academy prospect, 17-year-old De Girolamo, was on the bench, along with Chapell, recalled from a loan spell at Burton Albion on Monday.
Early indications - Cresswell firing at goal after 25 seconds - were misleading as a slow start from both sides failed to warm up the fans. It took 15 minutes for Coventry to threaten but Williams prevented McSheffrey meeting a Moussa cross and then Wood failed to connect with a Baker corner, despite the defender being unmarked.
Doyle, back at his former club, hammered a 30-yard volley which Murphy was forced to parry and Westlake's shot was too comfortable for the Coventry goalkeeper. At the other end, Baker's shot at Long was weak and Moussa sliced wide.
Just before the first half ended, Maguire fired a 30-yard free-kick just over the angle of post and crossbar, ensuring both sides had plenty to play for in the second period.
United were the first to show after the break and Flynn and Cresswell combined for Cofie to shoot but his effort was blocked and the unlikely source of Hill was the next to threaten Coventry. The defender intercepted and began a move which ended with a Cofie cross and the Blades number six throwing himself at the ball but he was unable to test Murphy.
However, the home side's first foray forward in the second half earned them a goal. On 58 minutes, Jennings provided the run and his low cross was turned into his own net by MAGUIRE, attempted to cut out the ball, which was aimed at McGoldrick.
The Blades hit back with a long ranger from Cofie and a Hill header from a McFadzean corner, whilst Wilson threw on Chapell and then Ironside and De Girolamo, the latter firing over with his first sight of goal.
De Girolamo then curled in the free-kick from which the Blades levelled on 81 minutes. The ball was half-cleared but Doyle's shot from 20 yards was only parried and McALLISTER was the first to react to slot the ball under Murphy, before heading off to celebrate in front of the Blades fans.
McAllister almost got on the end of a Flynn free-kick soon afterwards as the Blades looked more likely to sneak a victory, although Long had to save from an acute angle from McGoldrick, who also failed to get on a chipped cross from Baker.
Three minutes of added time was announced and McSheffrey's shot was weak, the only notable action before the final whistle, apart from words exchanged between McGoldrick and Maguire.
Coventry: Murphy, Baker, McSheffrey, Jennings, Christie, Wood, Edjenguele, McGoldrick, Moussa (Fleck 76), Bailey, Adams.
Unused: Clarke, Dunn, Barton, O'Donovan.
Blades: Long, Westlake, Maguire, Hill, Flynn, Doyle, McAllister, Cresswell (Ironside 72), Cofie (De Girolamo 72), McFadzean (Chapell 66), Williams.
Unused: Philliskirk, Coyne.
PENALTIES (Coventry first)...
McSheffrey - SCORED - 1-0
Ironside - SCORED - 1-1
McGoldrick - SCORED - 2-1
Maguire - saved - 2-1
Baker - SCORED - 3-1
Flynn - missed - 3-1
Fleck - SCORED - 4-1