Sheffield United boss David Weir admitted he was disappointed to exit the Capital One Cup following a 2-1 defeat to Burton.
Chris Hussey pounced twice in the second half, either side of Blades' skipper Michael Doyle's effort, to stun the home crowd.
But Weir insisted there was still plenty of positives to be taken from his side's performance in the first round.
"There were positives and also, of course, some negatives," the United manager said. "Obviously I'm not happy that we didn't go through.
"I thought we played well enough but there are things that we still have to work on. We saw some of those things out there.
"We know that ultimately we'll be judged on our ability to win football matches and we haven't done that here.
"We want to pass the ball, we want good movement and we want to play at a high tempo.
"But I come back to the fact we want to do that within a winning scenario."
Weir added: "We've got to look at why we conceded the goals we did. Discover why we did and work on ensuring it doesn't happen again.
"Like I say, it wasn't all bad. But obviously there is plenty we can do better."