Gillingham manager Justin Edinburgh felt his players shot themselves in the foot after surrendering 2-0 at Wimbledon.
Dominic Poleon capitalised on a loose pass back from Rory Donnelly to open the scoring.
The points were then sealed on the stroke of half-time when Dean Parrett scored from the spot after John Pask had hurled Paul Robinson to the ground.
Donnelly was sent off in the 89th minute but the damage had long since been done.
Edinburgh said: "I'm angry, frustrated and disappointed.
"Yet again we've been the instigator of our own defeat and downfall.
"It was an OK start for us. It was scrappy, competitive, what we were expected, physical but I thought we stood up to it.
"But then there's a couple of moments of madness.
"You're not going to continue week in, week out coming from goals behind and that's proven again.
"We've got to run harder, faster, further than we did in the second half. We've got to analyse that and that needs to be put right.
"I have to take responsibility for the players I put on the pitch and the teams I'm selecting so I can't hide behind that.
"We can't hide behind injuries for the goals we gave away. The back pass was suicidal and the penalty was the same."
Wimbledon had tossed away the lead in each of their last two games against Shrewsbury and Coventry, in both cases having to settle for a draw.
But boss Neal Ardley believes his team showed they have learned their lesson by seeing this one through.
Ardley said: "We have dropped some points lately from leads that we are disappointed with and it was more a case of the lads thinking this is not happening this time.
"Justin will be disappointed with both goals, they have handed us both goals with a sloppy back pass and then a stonewall penalty.
"From our point of view we have still got to take them. Dominic Poleon has still got to be ready to press the back pass which he was. Poleon took his goal brilliantly
"There was a bit of fatigue but we knew they were going to come out hard.
"I thought in the first half we were really good and good value. Our intensity was really good.
"In the second half, when you are 2-0 up, it is about being professional and seeing the job through and make sure we don't concede early in the second half like we did last week.
"In the second half we passed a bit better and were more free-flowing. here were loads of good performances out there."
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