Chesterfield boss Lee Richardson claimed his side had been daft in allowing MK Dons to leave Saltergate with a 2-1 victory.
The visitors moved back to the top of the table as a result of the win, while the Spireites missed out on a chance to inch back into the play-off places.
Richardson told the Sheffield Star: "It was a perfect illustration of our season, a missed opportunity. We're young and naive and a bit daft.
"We gave them a goal in the first half after I'd been really pleased with the approach and strategy to be patient in defence.
"It was all going fine until just before half-time when we switched off, didn't stick with their runners and we conceded a goal, so we went in on a downer.
"We got ourselves back in the game and then have a complete switch-off and we're 2-1 down."