Nigel Clough was brutally honest in his assessment of Saturday's fixture at Swindon Town.
A last minute goal from Louis Thompson saw the Blades slip to a 2-1 defeat.
Miles Storey gave Swindon a first half lead only for Michael Doyle to level as the Blades dominated the second half. United had the ball in the back of the net late on but the effort was disallowed and the visitors had a number of penalty shouts before Thompson won it.
Afterwards, Clough said: "There was an awful lot wrong in the first half, it appeared like a pre-season game to us. Travelling could be a factor, we've had a couple of long trips, but it played into the hands of Swindon, who operate at a slow tempo.
"We asked for a response at half-time, to play as we have done recently with energy, tempo, content and aggression. We have no problems with the second half but you cannot waste a half, not at this stage of the season.
"If we had played like we did in the second half in the first we would have won the game comfortably.
"We had a couple of great chances late on and then moments later the ball is in our net, we shouldn't have been broken down that easily, a number of senior players should have done a lot better."
Of the penalty incidents, the Blades chief added: "We think we should have had six penalties in the last three matches.
"There were three at Swindon, Brayford was dragged down in the first half, Porter in the second and then Freeman is bundled over again.
"The referee is looking at every one of them - we thought there were some staggering decisions."