Nigel Clough admitted he was a relieved man after seeing United leave it late to beat Gillingham on Saturday, although he felt the Blades were worthy winners in the end.
Jamie Murphy's fantastic solo effort deep into stoppage time completed a marvellous comeback for the Blades, who against the run of play, had fallen behind to a Luke Norris screamer for the Gills.
But Michael Higdon quickly levelled matters before Murphy last-gasp strike made it four wins on the spin at Bramall Lane in all competitions.
The Gaffer remarked: "We could and should have won the game comfortably, but in the first-half we didn't play with the same intensity as we did after the break.
"It is another win though, a thoroughly deserved one and the eventually manner of the victory shouldn't disguise the fact that we produced a very good performance and had enough chances to win two or three matches.
"We didn't have that bit of luck with the bounce of the ball off the woodwork, but Stephen (Bywater) who we know from our time at Derby produced several good saves as their goal led a charmed life.
"It was a totally domination for long periods, particularly in the second-half but you see a lot of games like that then a screamer goes in at the other end and often you don't get what you deserve, thankfully we did on this occasion."