Chesterfield came out on top in a pulsating derby with Sheffield United which saw five goals, two sent off and three points for the Spireites.
Jimmy Ryan got the ball rolling with a thunderous strike before the Blades were reduced to ten men when Michael Higdon was shown a straight red.
But the man advantage last little over ten minutes and Tommy Lee was given the same punishment for a trip on Jamie Murphy outside the penalty area.
It meant a re-shuffle for Paul Cook’s Chesterfield pack with 18-year-old Myles Wright introduced for his first league appearance.
Gary Roberts doubled the Spireites’ lead when he ran half the length of the pitch before the break before Eoin Doyle pounced from close range to make it three in the second half.
Wright, who was largely untested, was put under pressure late on by a resurgent Sheffield United side who reduced the arrears through Marc McNulty and Neil Collins.
But, on a day when supporters commemorated the career of Ernie Moss with a minute’s applause on eight minutes, Chesterfield survived to claim a memorable win.
Chesterterfield manager Cook made three changes to his starting line up to that which drew with Notts County seven days previous.
Roberts, Sam Morsy and Dan Jones all returned from hamstring injuries to bolster the Spireites side against an in-form Sheffield United.
They came in to the first eleven as Cook returned to his preferred 4-2-3-1 formation with Ollie Banks, Dan Gardner and Sam Clucas dropping to the bench.
The Blades, meanwhile, brought in on loan Paddy McCarthy from Crystal Palace just 24 hours previous and he went straight in to the centre of defence.
Both sets of players were greeted by a vocal reception by all four corners of a packed-out Proact Stadium - 9,723 in attendance for the lunch time kick off.
Chesterfield started brightly and got the ball on the deck, per their manager’s instructions, there didn’t seem to be any early nerves from the hosts.
The visitors had clearly singled out Morsy for special attention in the opening exchanges and Michael Doyle went in the book for a kick on the midfielder from behind.
The Spireites front men caused the visitors problems with their movement and a quick interchange between Dan Johnson and Roberts gave the former a sight of goal.
And just as it appeared that Johnson was about to pull the trigger, Craig Alcock shut the door with a last-ditched sliding tackle to prevent a shooting opportunity.
Ian Evatt was well positioned to halt Stefan Scougall’s charge in to the penalty area after the midfielder hadn bundled his way through a couple of challenges.
Chesterfield hearts were in mouths when Michael Higdon headed unmarked past Tommy Lee from James Wallace’s centre, only for the assistant’s flag to come to the hosts’ rescue.
The visitors began to look threatening on the break with Jamie Murphy and Scougall combining before Ryan made a crucial interception on the cover.
Murphy was it again moments later when he latched on to a precise through ball and charged past the Spireites’ last man Georg Margreitter.
The defender, on loan from Wolverhampton Wanderers, hauled Murphy down on the edge of the area and was cautioned with the visitors crying out for harsher punishment.
It proved a turning point as Chesterfield were ahead soon after with a stunning 25-yard drive from Ryan, which flew past the despairing dive of Mark Howard in the visitors goal and in to the corner of the net.
And it went from bad to worse for Sheffield United when Higdon was shown a straight red for a late challenge on Jones just before the half-hour mark.
But the man advantage lasted little over ten minutes when Lee was given the same punishment for a trip on Flynn, who had capitalised on a defensive mix-up and beaten the Chesterfield keeper to the ball just outside the area.
It was even numbers again in terms of players but the Spireites went even further ahead of the visitors when Roberts ran half the length of the pitch and slotted past Howard.
The winger on his return to the starting line up capitalised on a poor pass from McCarthy to Alcock - the on loan defender tried to make amends but glanced a header wide in the closing stages of the first half.
If the second half was to resemble anything like the first, the packed crowd inside the Proact Stadium would have seen one almighty derby clash. The Spireites, however, started where they had left off.
Roberts raced through on goal and looked to have been pulled back when he shaped to shoot but load appeals for a penalty were turned down by the referee, who would have almost certainly had to dish a third red card if he .
Sheffield United looked suspect on the break and when Johnson looked to take advantage with a charging run but was crowded out, ignoring Doyle to his right who was unmarked.
The Irishman got his chance moments later after good work by Morsy and Johnson found Doyle unmarked at the back post, but his header was cleared off the line by Neil Collins.
Morsy and Ryan missed the target with respective efforts before Chesterfield extended their lead through Doyle from close range when he was first to react to Johnson’s blocked shot.
Wright, who had largely been a spectator since his introduction, then had a moment he’d rather forget to allow McNulty in to reduce the arrears. Collins made it a tense final few moments for the Spireites with a pin-point header but the hosts held on for a memorable victory over their near neighbours.
Spireites (4-2-3-1): Lee; Darikwa, Evatt (c), Margreitter, Jones; Morsy, Ryan; O’Shea (Wright 42), Johnson, Roberts (Clucas 65); Doyle (Gnanduillet 75).
Subs not used: Raglan, Banks, Boco, Gardner
Blades (4-5-1): Howard; Alcock, McCarthy, Collins, McEveley (Harris 66); Flynn (Campbell-Rice 63), Doyle (c), Wallace (McNulty 50), Scougall, Murphy; Higdon
Subs not used: Turner;, Basham, Davies, Reid
Goals: Ryan 25, Roberts 44, Doyle 74 (Chesterfield); McNulty 79, Collins 90 (Sheffield United)
Sendings off: Lee 40 (Chesterfield); Higdon 28 (Sheffield United)
Bookings: Margreitter 17 (Chesterfield); Doyle 7, Scougall 24 (Sheffield United)
Referee: Mark Brown (East Yorkshire)
Attendance: 9,723 (1,957).