Nigel Adkins acknowledged Saturday's 1-0 reversal at Crewe Alexandra was a difficult loss to accept.
Ryan Colclough scored the decisive goal of the game in the second-half for the Alex, but speaking afterwards the Blades bossed bemoaned his side's missed chances, especially those in the first-half.
The Gaffer reflected: "We lost the game, so it's a disappointing defeat. There is an expectation for us to be winning football matches and we haven't done it against the bottom of the league.
"We made a few changes, started brightly and could have scored on a number of occasions. The fact of the matter is we didn't and at the other end we have been punished and conceded another poor goal, despite having bodies there to deal with both the first and second ball.
"We will find out a lot about the players now in terms of character, because we have to put this behind us and go again in a positive manner."
Adkins, who refused to make excuses for weekend defeat, continued: "We won't hide away from these disappointments but we have to believe, I will reiterate what I have said since day one, there are no easy games in this division.
"The first goal in games is crucial we have emphasised that to the players, so when we don't take our chances it gives the opposition something to hold on to and when they score it increases their belief.
"Give Crewe credit they dug in and went on to get the victory, but for me we have to do more, we need to be more ruthless in both penalty areas and clinical in front of goal."