Alex Gilbey fired the Dons ahead with a fine strike before Jordan Clark equalised for the visitors.

But Collins’ penalty won the match to condemn Luton to a third defeat in their last four games.

The opening goal came after 25 minutes as MK Dons captain Gilbey eluded two defenders then fired a volley from the right flank beyond the reach of Luton goalkeeper James Shea.

The Hatters missed chances to level as home keeper Will Dennis denied Kasey Palmer and Jamie Donley.

MK Dons missed chances for a second after the break, with Eli Campbell heading wide and Sam Nombe’s deflected strike narrowly failing to cross the line.

Luton equalised in the 70th minute as Tudor Mendel teed up Clark to fire home from the edge of the box.

The winning goal came from the penalty spot nine minutes later. George Johnston bought down Collins, and the Dons’ top scorer beat Shea from 12 yards.