Gary MacKenzie netted his first MK Dons goal to help them to an impressive 1-0 win over local, and play-off, rivals Peterborough United at stadiummk.
A second-half toe-poke, after Posh goalie Joe Lewis spilt the ball,&nbsp;from centre-back MacKenzie ensured the Dons strengthened their position in the League 1 play-offs, where they now sit in fifth place with a eight point safety net.
MacKenzie was once again superb in defence to help the Dons keep a clean sheet against the League's top scorers. Peterborough had chances of their own as George Boyd rattled the post but the Dons' grit and desire shone through in another brilliant display from Karl Robinson's men.
Gary MacKenzie wheels away to celebrate&nbsp;his winner
The two form teams in the League were always expected to produce an action-packed 90 minutes, and from the first minute they both showed attacking intent as Stephen Gleeson forced an early save from Lewis second before the Dons' own goalkeeper David Martin, fit again after an ankle injury, was called into action by a tame effort from Tommy Rowe.
Posh made sure they tested the Dons' defence in the opening phases as Lee&nbsp;Tomlin first found space to shoot from 20-yards but lacked the composure needed as he blazed over.
The former Rushden and Diamonds forward then had his second and third chance of the game when Kouo-Doumbe's clearance from a throw-in fell at his feet, once his initial shot was blocked Tomlin tried again and this time only a superb tip away by Martin could deny him.
The resulting corner found Charlie Lee whose half-volley hit the ground and despite the late bounce Martin was able to produce a fine save at his right post.
Kouo-Doumbe and MacKenzie rise above the defence
Peterborough looked to be edging ever closer to the break through when Craig&nbsp;Mackail-Smith, voted League 1 Player of the&nbsp;Year,&nbsp;was released through by Rowe, yet with the ball stuck under his feet MacKenzie hassled the striker off the ball allowing Dean Lewington to clear up as Boyd pressurised.
It was a case of holding firm and hitting Posh on the counter-attack for the Dons, and when they did it the warning signs were there for Darren Ferguson's men as Peter Leven opened up his body to unleash a wonderful strike from distance for Lewis to push over.
Gasps were heard loud and clear at stadiummk in the 28th minute when the busy Boyd, covering every inch of the pitch, went unnoticed in the left of the Dons' box and smashed the ball against the far upright.
With Peterborough causing a scare the Dons rallied to push forward, which they were able to do when Lewington stopped an advancing Mark Little in his tracks to send the Dons up field. When the ball finally came back to the left-back he delivered an accurate cross but Woodards could not find his way through Posh's solid defence.
Sam Baldock fires in a shot as the Dons create chances
As expected, the chances continued to come for both sides as Martin blocked a shot from Boyd and then combined with MacKenzie to deny Mackail-Smith the follow-up.
The Dons finished the first half strongly as Chadwick ran rings around Rowe, who was trying his best to mark the midfielder, to move from the centre to the right touchline and back into the middle before stinging Lewis' palms.
The drama did not stop there as just a minute from the break Leven was afforded the space to drift to the left of the box and rattled the post with a fierce drive.
Five minutes into the second half the Dons enjoyed a healthy spell in Peterborough's half and Sam Baldock began to cause problems for the visitors' backline. The striker's touch on to Leven's delivery allowed him to turn the defender only for Lewis to boldly block with his body at the near post.
Baldock was involved in another half-chance for the Dons when he was found by a great ball from Leven only for his cross into Daniel Powell to be intercepted by Ryan Bennett.
There was little time to catch a breath in between the opportunities carved by either side as Tomlin again tested Martin with a low drive before the Dons' number one bravely ended a run by Mackail-Smith in a one-on-one chance.
Skipper Lewington gets beyong Mark Little
With little over an hour on the clock Robinson brought on Keanu Marsh-Brown to inject some pace into the game, and it worked a treat as the winger's speed earned the Dons a free-kick.
Leven's delivery was cleared to the far touchline where Chadwick played Kouo-Doumbe into the action. The Frenchman lifted the ball into the box&nbsp;and Posh goalie Lewis&nbsp;failed to keep hold of the ball allowing MacKenzie's outstretched foot to prod the ball home, sparking wild celebrations from The Cowshed.
The goal gave the Dons another gear and they could have so easily doubled their lead when Marsh-Brown terrorised full-back Little to move into the box and narrowly curl a shot over the bar.
Tom Kennedy keeps an eye on Daniel Powell
Given the goal scoring prowess of Peterborough their supporters behind the goal must have expected an equaliser when a inch-perfect cross came in for Nathaniel Mendez-Laing, but the substitute skied his effort high into the stands for 10-yards.
Fellow Peterborough sub David Ball edged closer with a point-blank effort, yet once again Martin, in inspirational form, lifted the ball away for a corner.
The closing moments could have been less nervy for the Dons when Powell's run down the right flank allowed Marsh-Brown to ghost into the box poke the ball wide and Jabo Ibehre hit a shot straight at Lewis.
And as it turned out the second goal wasn't' required from the Dons as they held on for three points that could have a huge impact on their quest for the play-offs.
MK Dons (4-2-3-1): Martin; Woodards (O'Hanlon 90), MacKeznie, Kouo-Doumbe, Lewington (c); Gleeson, Leven; Powell, Chadwick (Ibehre 77), Vine (Marsh-Brown 62); Baldock.
Subs not used: Searle, Stirling, O'Hanlon, Balanta, Chicksen
Goal: MacKenzie 69
Peterborough United (4-4-2): Lewis; Little, Bennett, Zakuni, Kennedy; Boyd, Lee (Davis 70), McCann (c), Rowe (Mendez-Laing 76); Mackail-Smith, Tomlin (Ball 76).
Subs not used: Langmead, Wesoloski, Basey, Jones
Booked: Tomlin, Zakuani
Referee: Graham Scott (Oxfordshire)
Attendance: 10,019 (1,729 away)