Bradley Johnson and Jack Tucker both netted to give relegation-threaten and managerless MK Dons a 2-0 League One victory over Portsmouth at Fratton Park.
Dons sacked Liam Manning after a fifth-straight winless league game last week, but long-serving player Dean Lewington masterminded a much-needed win as interim head coach.
Denver Hume and Josh Koroma had both been denied for Pompey before Clark Robertson struck the crossbar from a free-kick.
But when the visitors gained a foothold, veteran Johnson nodded in Conor Grant’s wicked cross for his fifth goal of the season.
Koroma thought he had equalised when he got in behind and put the ball past Jamie Cumming but was flagged offside.
Pompey fumed as they believe the ball had been played by a defender.
The home fans’ anger rose another notch when a poorly-defended corner was able to be poked in by Tucker at the far post as he celebrated his first Dons goal.
It led to chants of “this is embarrassing” as Pompey lost at home for the first time since January and saw their run without a league win extended to six matches.