Marlon Harewood may have ended Hammers' 11-hour goal
drought but his fourth-minute strike was still not enough to
prevent Alan Pardew's men from crashing out of the Carling Cup
on a flat night at Saltergate.
Second half goals from Colin Larkin and Caleb Folan condemned West Ham United to a club record eighth successive defeat on a night when Chesterfield added their name to the list of giant-killers who have felled the east enders down the years.
No fewer than 40 rungs had separated the two sides, with Hammers languishing in 19th spot in the Premiership and Roy McFarland's team sitting in 15th place in League One.
But after slumping to a seventh straight defeat at Tottenham Hotspur on Sunday, Pards was only too aware of the potential banana skin awaiting his side on a damp, Derbyshire night in late October.
Indeed, four seasons earlier, his predecessor Glenn Roeder had brought a star-studded selection of eight current and future internationals - plus skipper Paolo Di Canio - to Saltergate, where the Hammers finally prevailed 5-4 on penalties following a hard-fought 1-1 draw.
Pards made a trio of changes from the side that lost at White Hart Lane as debutant George McCartney replaced substitute Paul Konchesky at left back, while Christian Dailly and Kyel Reid came in for Javier Mascherano and the injured Yossi Benayoun.
Following Saturday's defeat at Doncaster Rovers, McFarland recalled Kevan Hurst and striker Larkin, who worryingly forced Robert Green into a defiant, early, full-length save after Folan carved the West Ham rearguard open with a defence-splitting pass.
But the Hammers' 'keeper quickly turned from goal-saver to goal-maker when he launched a massive fourth-minute drop-kick upfield, where Reuben Hazell's hesitant header skywards was brutally punished by Marlon Harewood, who volleyed home from 18 yards to end his side's 672-minute goal drought.
The relief that West Ham had finally found the net after a seemingly eternal, 11-hour wait was there for all to see as the striker's nine outfield team-mates ran to celebrate his first strike of the season.
Five-goal Bobby Zamora then sent a low, angled 15-yarder across the face of goal, while at the other end, the lively Larkin and feisty Folan eagerly chased anything that came their way as the Spireites forced five corners without reply in the opening 25 minutes.
On the half-hour mark, John Pantsil was harshly booked for a fair, albeit forceful, aerial challenge with Hurst and, as confident Chesterfield continued to search for a leveller, Harewood was cautiously withdrawn into a deeper midfield role.
And after both Mark Allott and Derek Niven had sent long-rangers narrowly off target, Hammers had Green to thank for preserving their interval lead when he gratefully gathered Aaron Downes' acutely angled, 41st-minute shot at the base of his left-hand post.
Five minutes into the second period, Larkin almost made Danny Gabbidon pay the price for an unfortunate slip, however he hooked the ball over both the advancing Green and the West Ham crossbar, to the relief of the Welsh defender.
But the Spireites' striker was not to be denied. On 53 minutes, the lethal Larkin crashed home the rebound from eight yards after the Hammers' 'keeper had acrobatically tipped Folan's scorching 18-yarder onto his right-hand upright.
With Teddy Sheringham already on the field for the hobbling Harewood, Matthew Etherington soon replaced the subdued Reid and Konchesky switched places with McCartney.
McFarland was forced to bring on Jamie Lowry for the injured Alex Bailey, too, and with the game ebbing and flowing from end to end it really was anybody's tie.
Hayden Mullins saw his low, 25-yarder held by Barry Roche, Sheringham had a couple of efforts charged down and the unmarked Zamora somehow sent a volley over the top from just 12 yards.
Chesterfield, meanwhile, took the corner count into double figures and with the Hammers' penalty area, coming under sporadic siege, both Hurst and Niven forced Green into awkward saves.
Only eight minutes were left on Referee Probert's watch, when Sheringham invited Zamora to break the Chesterfield resistance, once and for all, but the Hammers striker saw his wasteful, low shot diverted wide by Roche's outstretched leg.
That was to prove a costly miss. For when Etherington committed an 87th-minute foul out on the touchline, Alan O'Hare's subsequent free-kick was only half-cleared by Sheringham to Paul Hall, whose touch allowed Folan to gleefully bury the lose ball with a clinical eight-yarder, securing Chesterfield's place in the fourth round.
Second half goals from Colin Larkin and Caleb Folan condemned West Ham United to a club record eighth successive defeat on a night when Chesterfield added their name to the list of giant-killers who have felled the east enders down the years.
No fewer than 40 rungs had separated the two sides, with Hammers languishing in 19th spot in the Premiership and Roy McFarland's team sitting in 15th place in League One.
But after slumping to a seventh straight defeat at Tottenham Hotspur on Sunday, Pards was only too aware of the potential banana skin awaiting his side on a damp, Derbyshire night in late October.
Indeed, four seasons earlier, his predecessor Glenn Roeder had brought a star-studded selection of eight current and future internationals - plus skipper Paolo Di Canio - to Saltergate, where the Hammers finally prevailed 5-4 on penalties following a hard-fought 1-1 draw.
Pards made a trio of changes from the side that lost at White Hart Lane as debutant George McCartney replaced substitute Paul Konchesky at left back, while Christian Dailly and Kyel Reid came in for Javier Mascherano and the injured Yossi Benayoun.
Following Saturday's defeat at Doncaster Rovers, McFarland recalled Kevan Hurst and striker Larkin, who worryingly forced Robert Green into a defiant, early, full-length save after Folan carved the West Ham rearguard open with a defence-splitting pass.
But the Hammers' 'keeper quickly turned from goal-saver to goal-maker when he launched a massive fourth-minute drop-kick upfield, where Reuben Hazell's hesitant header skywards was brutally punished by Marlon Harewood, who volleyed home from 18 yards to end his side's 672-minute goal drought.
The relief that West Ham had finally found the net after a seemingly eternal, 11-hour wait was there for all to see as the striker's nine outfield team-mates ran to celebrate his first strike of the season.
Five-goal Bobby Zamora then sent a low, angled 15-yarder across the face of goal, while at the other end, the lively Larkin and feisty Folan eagerly chased anything that came their way as the Spireites forced five corners without reply in the opening 25 minutes.
On the half-hour mark, John Pantsil was harshly booked for a fair, albeit forceful, aerial challenge with Hurst and, as confident Chesterfield continued to search for a leveller, Harewood was cautiously withdrawn into a deeper midfield role.
And after both Mark Allott and Derek Niven had sent long-rangers narrowly off target, Hammers had Green to thank for preserving their interval lead when he gratefully gathered Aaron Downes' acutely angled, 41st-minute shot at the base of his left-hand post.
Five minutes into the second period, Larkin almost made Danny Gabbidon pay the price for an unfortunate slip, however he hooked the ball over both the advancing Green and the West Ham crossbar, to the relief of the Welsh defender.
But the Spireites' striker was not to be denied. On 53 minutes, the lethal Larkin crashed home the rebound from eight yards after the Hammers' 'keeper had acrobatically tipped Folan's scorching 18-yarder onto his right-hand upright.
With Teddy Sheringham already on the field for the hobbling Harewood, Matthew Etherington soon replaced the subdued Reid and Konchesky switched places with McCartney.
McFarland was forced to bring on Jamie Lowry for the injured Alex Bailey, too, and with the game ebbing and flowing from end to end it really was anybody's tie.
Hayden Mullins saw his low, 25-yarder held by Barry Roche, Sheringham had a couple of efforts charged down and the unmarked Zamora somehow sent a volley over the top from just 12 yards.
Chesterfield, meanwhile, took the corner count into double figures and with the Hammers' penalty area, coming under sporadic siege, both Hurst and Niven forced Green into awkward saves.
Only eight minutes were left on Referee Probert's watch, when Sheringham invited Zamora to break the Chesterfield resistance, once and for all, but the Hammers striker saw his wasteful, low shot diverted wide by Roche's outstretched leg.
That was to prove a costly miss. For when Etherington committed an 87th-minute foul out on the touchline, Alan O'Hare's subsequent free-kick was only half-cleared by Sheringham to Paul Hall, whose touch allowed Folan to gleefully bury the lose ball with a clinical eight-yarder, securing Chesterfield's place in the fourth round.