Nigel Clough says being ruthless in front of goal in Monday's Sky Bet League One play-off semi-final second-leg against Swindon Town is crucial to the Blades chances of progressing to the Wembley final where Preston North End would be standing between them and the Championship.
United head to the Country Ground trailing 2-1 from the first-leg after Nathan Byrne's last-gasp winner for the Robins, but ahead of the return in Wiltshire, Clough insists nothing is lost in the tie.
The Gaffer remarked: "We didn't learn anything we didn't already know about Swindon on Thursday night and they will probably be saying the same about us.
"We knew we could force mistakes high up the field if we pressed them in possession and for the first 30 minutes we absolutely dominated.
"So that is encouraging and despite them having a goal advantage there is still everything to play for."
Clough has acknowledged the first goal on Monday evening could have a big say on the eventual winners of the contest and although he his mindful of Town's threat going forward, the Blades boss is urging his players to be positive.
He concluded: "We also had a spell in the second-half where we created two or three good chances, what we have to do in the second-leg is convert those chances, because we are confident we can get at Swindon again.
"But equally so, we know we will have to keep our shape and work extremely hard out of possession because with or without a lead they will always look to dominate the ball and control the tempo of the game.
"They did that in spells at Bramall Lane and if we don't defend properly as a team then they are capable of hurting us."