Head coach Michael Skubala felt his team needed to be more ruthless in their 1-0 home defeat to Chesterfield in the group stages of the Bristol Street Motors Trophy.
Connor Cook scored the decisive goal for the Spireites early in the second half.
Skubala said: "I thought in the first half we played well, putting the ball into the box, making them defend, and getting around their sides. We were effective and moved the ball through them very quickly.
"In the second half, we didn't look like ourselves. We had some possession but didn't put them under enough pressure. It felt like the game against Harrogate (in the Carabao Cup), where we were caught on the counter-attack and ended up chasing, which made us lose our identity and the way we want to play.
"Sometimes that's the nature of having changes and new players out there, as it can disrupt the rhythm a little bit. We didn't return to the levels we reached in the first half. We should have been more ruthless then, and in the second half, we didn't show any of that.
"We have a lot of work to do in that regard, especially when we don't score; we need to stay focused. We must ensure we continue working on our composure and decision-making in the final third."
Speaking about debutant Erik Ring and Lewis Montsma getting valuable game time, he added: "Erik did well and looked good in some moments. He's still adjusting to how we want to play. I thought he was quite aggressive and exciting in the first half. He hasn't had many minutes and felt it in his legs, which is why we took him off. We need to build him up, but he'll do well here.
"Lewis has been training a lot, and this competition is a good opportunity for him to get 90 minutes under his belt."
