WATCH: MK Dons go 11 without at win at Stadium MK
Port Vale won their first away game since April as MK Dons miserable home record continued on Sunday.
Dons looked in total control of the game, with first Kieran Agard and then Dean Lewington coming close, before the Dons captain handled in the area to allow Vale their first opening 10 minutes before the break.
Lewington's handball appeared to be appeased when David Martin saved Alex Jones' penalty, but the rebound fell nicely for the Vale striker, who tapped into the empty net.
Dons huffed and puffed in the second half but were restricted to half-chances, though Ben Reeves thumped the bar in stoppage time.