Charlton boss Phil Parkinson accepted responsibility after his side crashed out of the Carling Cup with a 4-3 first-round defeat at npower League Two outfit Shrewsbury.
The Addicks surrendered a 3-0 lead to exit the competition at the first round stage for the third successive season.
Parkinson made several changes to his side and said: "I take responsibility for those changes but it was good experience for our younger players."
He added: "Shrewsbury are a good side and they played well on Saturday too. After we were three goals up we had enough chances to put the game out of sight and we have to get over this because we have a big game on Friday.
"Any defeat is damaging so we have to make sure that we are far more compact. We were far too open in our defence in an end-to-end game.
"We probably got a little bit over-confident and became sloppy. Their first goal was just a long ball which we should have dealt with easily. Although we gave away four goals Ross Warner did well in goal. He dealt well with some of the crosses and distributed the ball well."
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