Ched Evans limped off in a second half horror show for Chesterfield, losing 4-1 to Sheffield United having led at the break.
Jon Nolan’s second minute opener separated the two sides after a pleasing first half for Town.
United will have gone in aggrieved by the number of great positions they wasted, but their hosts just couldn’t live with them, wilting under a second half onslaught.
After Kieron Freeman’s equaliser, two goals in the space of a minute midway through the second period took the game away from the Spireites completely.
And Leon Clarke added a fourth late on to compound the misery for Chesterfield, who also lost Nolan to injury.
The deafening chants from the packed away end were silenced by Town’s perfect start, Nolan scoring a quite stunning goal after just two minutes.
Former Blade Evans brought the ball inside and laid it off to the midfielder who thundered a half volley past Simon Moore from a tight angle.
United settled well after the goal, keeping the ball and eventually working it forward to Dan Lafferty who shot from the edge of the box but failed to trouble Ryan Fulton.
Chesterfield saw plenty of possession in the first quarter of an hour, but were guilty of giving it away carelessly. Nolan’s poor pass deep in the United half very nearly cost them, the Blades attacking with pace through Matt Done whose cross was met by Kieron Freeman, Fulton saving well.
Gboly Ariyibi was responsible for one or two bright moments, whipping in a dangerous low cross that none of his team-mates could reach and then skipping past a marker and drawing a foul, allowing Evans to have a crack at goal from the free-kick, albeit straight into the wall.
For the Blades Billy Sharp had a half chance on the half hour mark, controlling a low cross well and turning to shoot but slicing well wide.
As the visitors began to ascert control, Town found themselves dropping deeper and almost inviting shots from distance, Mark Duffy obliging twice, his first hopelessly wayward and his second comfortably saved.
For all their possession and territory, United were lucky not to head into the changing room 2-0 down after a corner late in the first half was headed onto the crossbar by Ian Evatt.
It was straight back on the attack for the Blades after the interval, but again the Spireites could have doubled their lead, breaking out on the counter through Evans who brought a smart stop from Moore from an impossible angle.
At the other end Fulton denied Sharp with a fine save at his near post, but there was nothing he could do on 54 minutes when a cross was whipped in from the left by John Fleck and Freeman arrived, unmarked to head home the equaliser.
Freeman, who was booked for celebrating with the fans behind the goal, was almost in for a second when Fulton misjudged a bouncing ball and then had to dive backwards to claim under pressure.
United had a let off of their own when Nolan slipped the ball to Evans and his shot was partially saved by Moore, Jake Wright having to head off the line before his keeper eased Evans off the rebound - halfhearted penalty appeals ignored by referee Christopher Sarginson.
That was Evans’ last contribution, all four stands rising to applaud the Welshman as Kristian Dennis took his place.
Town breathed a huge sigh of relief less than a minute later, Blades breaking with pace, Done somehow sending the ball skyward via the top of the bar after a lovely ball in from Duffy.
And in worrying scenes for the hosts, Nolan limped off having picked up a knock, Ritchie Humphreys making a somewhat unexpected appearance.
Things got much worse when Sheffield United took complete control with two goals in a minute.
Fleck put them in front when he set his sights from 25 yards and let fly, Fulton well beaten by the fierce low effort.
He was picking the ball out of his net again seconds later, Duffy supplying the cross, Sharp rising to head home at the back post and send the visiting supporters into raptures.
With nine minutes remaining Leon Clarke added the icing on the cake, the substitute simply rolling the ball past Fulton from outside the area with a lovely finish.
The home fans almost had something to cheer late on but when Ariyibi played in Jay O’Shea he put the ball wide when it seemed harder to miss than score, capping a dreadful second half for Danny Wilson’s men.
Chesterfield: Fulton, Liddle, Evatt, Anderson, Donohue, Dimaio, O’Neill, Nolan (Humphreys 69), Ariyibi, O’Shea, Evans (Dennis 66). Subs: Mitchell, Allinson, Simons, Maguire, German.
Sheffield United: Moore, Freeman, Ebanks-Landell, Basham, Wright (Clarke 68), Lafferty, Coutts, Fleck, Duffy, Sharp (Lavery 90), Done (O’Connell 78). Subs: Long, Scougall, Brown, Whiteman.
Referee: Mr Christopher Sarginson. Assistants: Mr Marvyn Amphlett, Mr Nicholas Barnard.
Goalscorers: Nolan 2; Freeman 54, Fleck 72, Sharp 73, Clarke 81
Yellows: Freeman 54