Nigel Clough conceded the Blades had a 'really bad evening' as they bowed out of the FA Cup at the fourth round stage with a 3-1 defeat against Preston North End at Bramall Lane.
With a fifth round home tie against Manchester United the prize for the winner, United surrendered the half-time advantage given to them by Jamie Murphy, as former loanee Paul Gallagher netted twice, the second coming from the penalty spot as North End scored three times in ten second-half minutes to settle the contest in their favour.
A disappointed Clough offered no excuses afterwards, remarking: "Preston came and did a job on us, they stopped us playing and thoroughly deserved the win.
"They changed their formation to try and stop us in wide areas and if we are being honest we never really got going.
"We have to give Preston a lot of credit for the way they came and created a host of chances and took the game to us, but we also need to have a look at ourselves.
"Their determination seemed a bit stronger than ours which is disappointing with what was at stake and unlike in the previous three fixtures against them we didn't handle Kevin Davies.
"We said before the game we couldn't afford to be giving free-kicks away in and around the box because Paul Gallagher has the quality to punish you and he did it again just like he did at Deepdale."
The Gaffer added: "Taking everything into account it was a really poor evening, we are disappointed with the manner of the defeat and aspects of our performances, but ultimately we have also missed out on a fantastic opportunity to host Manchester United at Bramall Lane.
"We rested players at the weekend so we would have that spark and energy about us, but it didn't happen and that performance emphasised why we needed to be active in the transfer window."