Chris Wilder's stretched Blades suffered a narrow defeat at Preston on Saturday.
Jordan Hugill scored the only goal as the Blades gave a league debut to Academy graduate Regan Slater after injury, suspension and illness depleted the visitors to Deepdale.
Carter-Vickers and Carruthers returned to the starting XI, replacing the suspended Fleck and ill Duffy. On the bench, Lavery, Heneghan and youth team skipper Slater were included -Brooks was also ill and missed out.
It took 35 seconds for United to be gifted a chance at Deepdale. Clarke cut out a clearance from goalkeeper Maxwell but the leading scorer's subsequent shot was blocked. O'Connell also headed over a deep Lundstram cross in an attacking start.
Preston's early threats centred around the movement of Robinson. He had already had a sighter before forcing Moore to push over a drive on 18 minutes.
A cross/shot from Basham caused Maxwell to scamper across his goal but the effort was just too high and United were up on the first half corner count but neither sides could lay claim to bossing the game.
As half-time approached Gallagher fired over and then, on 40 minutes, the former Blades loanee curled a free-kick which clipped the top of Moore's crossbar.
Preston did, though, make a better start to the second period and a heavy touch from Barkhuizen was a let off for the Blades. On 53 minutes Barkhuizen was involved again, leading a breakaway but Robinson dragged his shot wide.
The Blades were forced to replace Baldock with Lafferty, which meant a new position for Basham but Preston grabbed the lead with their next attack. Robinson's cross from the left saw HUGILL get around the back of the rearguard to sidefoot past an exposed Moore.
Robinson's long-range shot was saved by Moore but Preston were on top, which forced Wilder to make a couple of substitutions - including a league debut for Slater - and a change of shape.
As the game entered the final ten minutes, Preston began to defend deeper as the Blades looked for a route back in to the game. On 85 minutes Clarke's poke towards goal was kicked away by Maxwell but the striker was adjudged offside, although he received the ball from a North End defender.
Late on, Hugill had an opportunity to double his tally but his shot was deflected wide and United's last chance, in three minutes of added time, was a long-ranger from O'Connell, which was off target.
Preston: Maxwell, Pearson, Clarke, Hugill, Johnson, Gallagher (Browne 77), Fisher (O'Connor 28), Davies, Huntington, Barkhuizen, Robinson (Harrop 77).
Unused: Rudd, Boyle, Horgan, Mavididi.
Blades: Moore, Baldock (Lafferty 58), Stevens, O'Connell, Basham, Lundstram, Clarke, Sharp, Carter-Vickers (Donaldson 68), Stearman, Carruthers (Slater 74).
Unused: Wright, Lavery, Heneghan, Blackman.