Chris Wilder acknowledged his side need to be 'better in the key moments', following Saturday's loss against Derby County.
Chris Basham cancelled out Craig Bryson's first minute opener at Pride Park, but Jack Marriott won it for the Rams in the second-half, to leave the Blades boss frustrated.
And he pulled no punches afterwards, remarking: "I won't dress it up at all, we've lost the game of football and second-half we didn't do enough with or without the ball to get a result, it's as simplistic as that.
"They've won, we've lost there's nothing else that needs to be said really, it's pointless saying about a load of other things.
"I don't think we should have lost the game, but we have. We have to be better in the key moments, if we are to carry on adding to our points tally like we have done.
"I'm straight down the middle, we've lost, I've said to them it's nonsense people saying it was a great game, it isn't when you lose, it's fantastic if you win."
Wilder added: "I'm always hard nosed and you have to be. People aren't putting arms round my uncle or brother, or fans who have to go to work after a defeat.
"I'm not going to go putting my arm around them, they've lost the game. Defend properly, stop the cross and track the runner.
"When we are at the top of the pitch, the likes of Duffy and others need to be better and finish off good play.
"In big games players need to come up with the goods, we've not been appalling, it's not a particularly bad performance but it's a loss and we need more from the players."