The script was torn up in a second half that saw Chesterfield's hopes of another victory shattered by a spirited MK Dons comeback.
Roy McFarland's team were heading for an eighth consecutive home league win for the first time in 14 years when they moved into a 2-0 lead shortly after the break.
But the Dons kept going and got a deserved equaliser when substitute Wade Small headed them level two minutes from time.
The final scoreline was about right because better finishing would have put the visitors in the box seat before Chesterfield took the lead.
Izale McLeod should have scored in the ninth minute and it needed a sharp save from Carl Muggleton to deny Steve Palmer.
When Chesterfield did score it was against the run of play but Tcham N'Toya-Zoa finished clinically to find the bottom-right hand corner after Wayne Allison had put him in.
McLeod should have equalised before the break but awful control allowed the ball to run through to Muggleton when the striker was ten yards from goal.
That miss was punished when Scott Bevan missed a corner and Aaron Downes headed in at the back post on his first appearance for the club.
But the Dons struck back when McLeod finally made a chance count after Muggleton had saved a low drive from Ben Chorley.
McLeod missed another great opportunity in the 85th minute when his point-blank range volley lacked the power to beat Muggleton but the Dons equalised with two minutes left.
Laurent Herve went past Downes and picked out Small whose stooping header from the edge of the six-yard box gave Muggleton no chance.