Gboly Ariyibi struck his third Sky Bet League One goal of the season to inspire MK Dons to a 2-0 victory over bitter rivals AFC Wimbledon.
Ryan Seager scored first for the visitors, silencing the raucous Kingsmeadow crowd before Ariyibi got Milton Keynes' second.
Lyle Taylor's saved second-half penalty hindered the Wimbledon fightback, with the defeat leaving them 16th in the table.
The deadlock between the sides was broken after just seven minutes, when Seager nudged home Osman Sow's low cross from the left.
Wimbledon enjoyed the majority of possession but Ariyibi doubled the advantage after 27 minutes, steering home into the far corner after a goalmouth scramble.
Neal Ardley's side were awarded a 63rd-minute penalty thanks to Scott Golbourne's handball, but Lee Nicholls matched Taylor's shot with a strong dive to his right.
Wimbledon keeper George Long kept the hosts in it with a spectacular save from substitute Robbie Muirhead, but Nicholls proved unbeatable at the other end.