Russell Martin said it was a catalogue of errors which cost Dons all over the pitch in the 4-0 hammering at the hands of Peterborough United on Saturday.
Mo Eisa's brace came after a wonderful effort from Marcus Maddison and an Ivan Toney header as Darren Ferguson's men cruised to a straight-forward win, inflicting the heaviest defeat on Paul Tisdale since he arrived at Stadium MK.
Speaking afterwards, defender Martin said there were a lot of issues Dons have to deal with before they head to Southend on Tuesday night for the Carabao Cup second round game.
"It was disappointing, as disappointing as we've been since the manager got here," he said. "The important thing is learning from it going forward. If you over-analyse everything, it becomes a minefield. The manager gets the details right, and we'll work on the biggest issues. It's difficult because we haven't got a lot of time on the training pitch, we've shown we're capable, but we can't have many more days like this.
"There's not one thing we can pinpoint. The first goal is brilliant, but we spoke about him before the game, keeping him off his left foot but we let him inside to shoot.
"The second one is soft from a free kick, and after that, it was really difficult. We had to open up and try and get a goal, but on a big pitch they found their groove and it got more difficult. We just weren't good enough on the day.
"The heat became more of a factor at 2-0 down. They managed it better. It makes it really hard to rally at 3-0 down though, swinging momentum in that heat. We didn't get going, and we have to be better at that in the long term. Now it's about how we bounce back, use it as a positive in terms of the season."
After four games this season, Dons have two wins and two defeats to their name. But after such heavy thumping, Martin said Dons have shown plenty of promising signs on their return to League One.
He said: "You always want another game quickly. We have still made a solid start in this league, today was humbling and it brings you back to earth.
"That Wycombe game could have gone either way, we could have won it and we could be stood here with three wins out of four. But it is what it is, we're a game behind, there is still plenty to be positive about and hopefully we'll be able to bounce back on Tuesday."