United's 16 game unbeaten start to the League One season came to an end on Saturday, courtesy of a late disputed penalty for the MK Dons.
Blades boss Danny Wilson was left 'angry and frustrated' at the manner of the defeat at stadium:mk, after referee Darren Sheldrake adjudged David McAllister had brought down Angelo Balanta in the box late on.
Speaking after seeing Shaun Williams win the match for the hosts from the resulting spot-kick, the Gaffer struggled to hide his emotions at the decision that swung the clash away from United who had battled gamely throughout
He said: "I think the referee got it wrong. He didn't give one in the first half and it was a penalty I will admit that.
"But it shouldn't make a difference, I hope when the performance of the referee is analysed he will hold his hands up and admit his mistakes.
"All you want is for the big decisions to be right and unfortunately they weren't to the standard everyone expects.
"The timing of the decision is frustrating enough but I honestly can't see what he thinks he has seen.
"I am really angry and frustrated that we have lost in these circumstances, our lads didn't deserve to lose the game given that performance."