Luke Moore struck for AFC Wimbledon as they held on to claim all three points against 10-man Wycombe Wanderers.
The visitors had captain Stuart Lewis dismissed early on for a challenge on George Porter.
Three minutes later, the Dons made their extra man count when Moore headed into the far corner.
Wycombe's Jon-Paul Pittman then forced a good save from Ross Worner and at the other end Chris Arthur almost doubled the lead when he hit the woodwork.
VIEW FROM THE DRESSING ROOM
Wycombe Wanderers boss Gareth Ainsworth told BBC Three Counties Radio:
"Very pleased with my players - I just asked them, can we put [this match] to bed and go beat Mansfield next week and everyone said 'yep, of course we can'.
"We weathered the storm, we weathered the first 15/20 minutes and that was part of our game plan.
"I thought we dealt with the system very well, even with 10 men, but having said that, you lose a man, and you're 10 men, it's difficult for 10 minutes never mind 70 minutes."