Substitutes Kristian Dennis and Dan Gardner earn Chesterfield all three points

Danny Wilson's super subs Kristian Dennis and Dan Gardner sunk managerless MK Dons and lifted Chesterfield off the bottom of the Sky Bet League One table after a roller coaster second half.Struggling Dons looked on course for victory when they struck twice in six second-half minutes. Daniel Powell (67) and substitute Ryan Colclough eased a night of mounting frustration in front of goal against the Spireites by edging the hosts 2-1 ahead after 73 minutes.But defensive frailties enabled Wilson's men to clinch their first away league win of the season as substitute Dennis lifted a shot high into the net before fellow replacement Gardner tapped in an 80th-minute winner.Dons dominated possession and chances from the first whistle only to fall behind after goalkeeper David Martin tripped Reece Mitchell. Former Don Jay O'Shea confidently slotted home the 32nd-minute spot-kick.Lively Kieran Agard smashed a shot against the post as Dons missed a host of chances before the late drama.