Kyle Vassell jumped off the substitutes bench to earn Peterborough United three precious points over the Milton Keynes Dons at London Road after a pulsating League One encounter.
Jon Taylor was a whisker away from a first Posh goal inside the opening three minutes, his free-kick finding the side-netting of the near post after Washington had been felled on the edge of the box.
Taylor tested MK Dons goalkeeper Dave Martin with a curler from 20-yards after a well-worked Posh corner kick on the 10 minute mark.
Ben Alnwick produced a save from the top drawer to deny Will Grigg, whose looping header was heading for the corner until the goalkeeper's intervention. Lewington fired over from the resulting corner kick.
Alnwick was called upon on 26 minutes to push a Bowditch drive over the bar as the Dons continued to create chances. Conor Washington created a chance out of nothing on the half hour mark, chasing a lost cause, shrugging off the attentions of McFadzean before seeing his low shot diverted wide by the feet of Martin at his near post.
Washington dragged a shot wide of the near post on 35 minutes as again the striker managed to wriggle clear of the Dons' centre backs. Anderson was cautioned five minutes before the break for a late foul before Reeves saw a shot deflected into the side-netting.
Mendez-Laing forced Martin into a superb stop on 41 minutes, the winger's effort from 30-yards was destined for the top corner until Martin produced the stop.
As the half moved into stoppage time, Posh found a breakthrough and there was no doubt a bit of luck was involved as Tottenham loanee Kenny MCEVOY saw his 25-yard right-footed effort loop over Martin and into the back of the net.
The goalscorer was replaced at the break with Kane Ferdinand introduced by boss Darren Ferguson. On 48 minutes, the visitors levelled and it was a bit of a dubious one as ALLI appeared to tap home from an offside position after Grigg's shot had deflected into his path.
Taylor headed a glorious cross from Smith over the bar moments later as Posh tried to reestablish their lead. The Dons introduced Afobe to replace Reeves just before the hour as Karl Robinson shuffled his pack.
Bostwick fired over with a free-kick as Posh introduced Kyle Vassell for Anderson. Bowditch sent a lob straight at Alnwick before Martin made a superb stop to beat away a fierce Vassell shot from 18-yards.
On 81 minutes, Posh got their noses in front as substitute Kyle VASSELL converted from close-range after excellent work down the left hand side.
Less than 60 seconds later, the Dons were back in the game and it was another substitute who netted, POWELL lofting the ball over the advancing goalkeeper as Brisley was beaten on the edge of the area.
Green fired wide of the near post after cutting inside from the left before five minutes of added time was indicated by the fourth official.
Final Score: Posh 3-2 Milton Keynes Dons
Posh: Alnwick, Smith, Ntlhe, Brisley, Bostwick, Taylor (sub Barnett 84min), Payne, Washington, Anderson (sub Vassell 73min), Mendez-Laing, McEvoy (sub Ferdinand 46min). Unused subs: Day, McCann, Newell, Santos.
MK Dons: Martin, Hodson, Lewington, McFadzean, Kay, Green, Green, Potter, Bowditch (sub Powell 79min), Reeves (sub Afobe 58min), Grigg (sub Randall 74min), Alli. Unused subs: McLoughlin, Flanagan, Baldock, Hitchcock.
Attendance: 7,115 (813 MK Dons fans)