The Spireites fell to only their second league loss of 2019 thanks to Akil Wright's winner as Wrexham ran out 1-0 victors at the Racecourse Ground.
John Sheridan made two changes to the side that beat Barnet 2-0 at the Hive on Tuesday; Tom Denton and goal scorer Charlie Carter made way for Jerome Binnom-Williams and Marc-Antoine Fortune.
Wright's 62nd minute header proved to be the difference between the two sides in a highly competitive fixture.
The first shot of the contest fell to the Dragons after five minutes. James Jennings let fly from 25-yards, but his effort flew over the crossbar.
Chesterfield’s first chance of the game came from Haydn Hollis’ clearance, as the centre-back swiped the ball away from the home attacker, but his effort sailed high and wide.
With just under 20 minutes on the clock, Curtis Weston came inches away from opening the scoring. His well-struck drive from the edge of the box clipped the top of the Wrexham crossbar.
Wrexham were presented with their best chance of the first half when Josef Yarney got caught in possession by Stuart Beavon, who threaded the ball through to Ben Tollitt but Shwan Jalal reacted brilliantly and quickly claimed the ball.
The second half started off rather slowly with Wrexham looking to turn the screw. However, every cross and attack saw a resolute Spireites defence clear their lines.
The visitors only forayed into the opposition box on a couple of occasions. Fortune over-hit a cross that was meant for Scott Boden, before the striker attempted an acrobatic effort that was easily collected by Rob Lainton.
Just after the hour mark, the league leaders got their goal - Luke Young’s inch-perfect cross found the head of an unmarked Wright, who headed past Jalal from close-range.
Barely a minute after the goal, Chesterfield very well could have been a man down, as a clearance fell directly into the hands of Jalal, but the referee adjudged the incident to be
outside the box. However, Carl Brook only gave the keeper a yellow.
With just over 20 minutes left on the clock, the Spireites had three golden chances to equalise. Chapman first tried his luck with a looping effort that was clawed out for a corner by Lainton.
From the resulting corner, Will Evans had a header cleared off the line before Denton headed over from a few yards during the same passage of play.
With five minutes to go, Jonathan Smith had a try from long-range, but it didn’t trouble Lainton and the home side gained all three points.
This loss sees the Blues drop to 19th, still four points above the drop zone and with a game in hand.
Chesterfield now travel to bottom of the table Braintree Town on Tuesday in what could be a big leap to survival.
Post-Match Verdict | Not the worst of losses
If you had offered a competitive 1-0 loss to most fans before the game, they may not like it but I think they would take it.
Chesterfield weren't up to the standards of Barnet or Fylde, but still looked good for a draw and probably should have had one.
However, a large portions of Spireites fans would rather see a win against Braintree on Tuesday to widen the gap to seven points from the drop zone.
Hopefully, Charlie Carter and Alex Kiwomya return for that game as Chesterfield missed that pace and quality against Wrexham.
Of course, a loss is disappointing, but a massive three points in midweek can suddenly change how the relegation fight is viewed once more.