Coach Neil Cluxton was left to reflect on the disappointment of an FA Youth Cup exit after seeing his side lose 2-1 at home to Burton Albion on Monday night.
Matt Fuertado put the young Spireites ahead before the visitors hit back to level virtually straight away and then struck the winning goal just before the break.
Assessing the game, Cluxton said: "Burton started the better and I thought they were very hard working and aggressive in their approach.
"They obviously reacted from the game two weeks ago when we beat them 2-1. They really showed their true colours last night and came out flying.
"Against the run of play, we took the lead through Matty Fuertado's deflected shot. We then made the cardinal sin of switching off straight away and I think we conceded within about 30 seconds, which deflated us a little bit.
"We didn't really get going at all in the first half and they deservedly got a second."
Cluxton felt it was an improved second-half display from his charges. He said: "We came in at half time and had a few strong words.
"We made two substitutions - Chad Gibson and Josh Turner came on - and we had a good go in the second half.
"We weren't great - we were just more aggressive and played a bit quicker. We had a number of what I'd call 'half-chances'. We had a lot of efforts that, unfortunately, either went wide or were skied over the crossbar.
"We pushed players forward a bit - young Jack Moore-Billam from the Under-16s came on for the last 15 mnutes and looked quite bright. We put Callum Brook up from the centre-back position to centre-forward and tried to get the ball in the box.
"We huffed and puffed without really looking like we were going to break them down. The lads did their best but I thought that on the night we were second best and I wish Burton all the best in the next round."
The youth team have a hectic schedule coming up with six or seven members of group set to turn out in tomorrow night's Derbyshire Senior Cup tie at Glossop North End, followed by Scunthorpe United at home in the EFL Youth Cup on Saturday.
That is followed by a trip to Salford in the same competition next Tuesday night and potentially a National League Cup game against York on the following Thursday and then a home game against Doncaster Rovers on Saturday, November 16.
"We've got games coming thick and fast now for the next couple of weeks, which is good because the lads enjoy playing and that's where we get to see what they're all about," said Cluxton.
"It's particularly important for the second-years because we're getting to the stage of the season where the club will start making decisions on players so they need to be performing in games."