Nigel Clough is confident of making further additions to his squad, after the Blades announced the signings of Marc McNulty and Jamal Campbell-Ryce on Monday.
McNulty joins on a three-year contract with United paying Livingston an undisclosed fee for his services, whilst Campbell-Ryce will officially become a Blades on 1st July on a free transfer from Notts County.
Speaking of his two newest recruits and the hope of completing more business, Clough remarked: "We are still looking for strikers, one, maybe two more.
"We were good defensively last season, now we need to score more goals and the more options we have the better.
"We are looking to balance the squad with a good mix of youth and experience, we can't play all the youngsters together, we need to offer them some support and that comes through having experienced heads around them.
"Like with all our signings Marc and Jamal are players we have monitored and tracked for a long time. We also look into their characters and the reports and feedback we got back were all positive.
"We will have no squad players to start with, we will have 18 or 19 competing for a spot in the starting XI and whoever is in form during pre-season will be in the team on the 9th August."
Clough also revealed that one player, who played for United's U21s towards the end of last season, with the view to signing in the summer, appears to be moving elsewhere, adding:
"Kevin (Stewart) looks to have decided to have joined a Premier League Club, he would have been a good addition but we will move on."