NIGEL Clough said defensive mistakes and missed chances cost his team a place in the last 32 of the Leasing.com Trophy.
The Brewers lost 2-1 to Mansfield Town at the Pirelli Stadium with David Templeton scoring for Albion.
Clough said: “For their first goal we gave the ball away twice within five seconds and if you do that in your own half you are going to get punished. Then we lost a man from a corner and he gets a free header and you are 2-0 down.
“It did feel like shooting practice at times at the end of the first half and their keeper made some great saves and we had balls going across the face of the goal which has been our problem all season.
“Scott Fraser and Colin Daniel have put some brilliant balls across and ultimately we have been lacking someone with the desire and that clinical sort of selfish attitude to say I’m going to get in the six-yard box.”
The Brewers had only needed a draw to go through but were edged out by the visitors.
Clough said: “We got the strongest back four we could with Lucas Akins at right back but when you concede a goal early that changes things and we shuffled things around, got some impetus and then it’s just about missed chances.”
Albion, already depleted by international call ups and injuries, suffered more blows when Jake Buxton and John-Joe O’Toole both had to go off with back problems and David Templeton with a knee injury.
Clough said: “It’s always a blow when you lose players. We are down to the bare bones. Oliver Sarkic and John Brayford both had to come on and neither of those two we wanted to risk tonight.
“The good news now is that we have an international break so we hopefully we can get a few bodies back.”