Blackburn returned to the League One summit after Adam Armstrong's first-half double helped secure a 2-1 victory over MK Dons.Peter Pawlett netted for the Dons midway through the second period during a spirited display from the hosts but it proved too little, too late as Dan Micciche's side slipped into the drop zone.Rovers did not have to wait long for the opener after Danny Graham's superb long-range pass from inside his own box saw Armstrong race through on goal, beat Robbie Muirhead for pace and fire a right-footed drive home.And the promotion-chasers' second came just before the break. Graham was again the provider with another accurate through-ball into the path of Armstrong, who cut inside on his left foot before firing an unstoppable effort past keeper Lee Nicholls.And despite Pawlett reducing the deficit, nodding home from Kieran Agard's excellent cross on 72 minutes, the Dons could not find a leveller as Tony Mowbray's side held firm.