The Spireites had to settle for a point after conceding a late equaliser in a 1-1 draw at Boreham Wood.
It looked like Chesterfield would deservedly take all the points back home following Akwasi Asante’s cool 82nd minute penalty.
But they failed to deal with a Josh Rees corner with two minutes to go as sub Adrian Clifton powerfully headed home.
The Spireites dominated the first 45 minutes with some slick passing and high energy football, pushing the Wood onto the back foot.
Chesterfield were unable to find the same performance levels after the break as Boreham Wood came out with more fight.
The Spireites made two changes from the side which drew 2-2 with Southend last time out, with Joe Quigley and Saidou Khan coming into the starting XI.
Boreham Wood included former Spireites Will Evans and Scott Boden.
Jim Kellermann miscued a long range effort on five minutes after a positive start from the Spireites.
Alex Whittle’s deep cross was just too high for Quigley as the Spireites continued to dictate the play.
Calvin Miller saw a shot blocked after Khan played him in before Boden blazed over.
Tom Whelan failed to hit the target from a great position as Chesterfield’s dominance increased.
Josh Rees looped a header onto the roof of the net, before Tyrone Marsh had a shot blocked for a corner.
Whelan curled a comfortable shot at Ashby-Hammond after an excellent turn by Khan in midfield kick-started a counter-attack.
Boden became the third Boreham Wood player to pick up a booking inside the opening half hour for a late tug on Whittle.
Rees fired inches wide after a surging run five minutes into the half.
David Stephens wasn’t far away as the hosts showed new purpose.
Whelan had a shot blocked for a corner on the hour-mark as Chesterfield looked to have weathered the storm.
Loach pulled off a brilliant diving save to keep out Rees on 72 minutes.
Chesterfield were given a life-line with ten minutes to go when Jacob Mendy Mendy was ruled to have handled a cross in the box. And Asante kept his cool from the spot to send the keeper the wrong way after a little shimmy.
But Chesterfield conceded with just two minutes to go as Clifton levelled from a Rees corner.
Loach, Grimes, Kellermann, Maguire, Whittle, Mandeville, King, Khan, Whelan (Asante 74), Miller, Quigley.
Attendance: 1,621 (570)