Matlock Town came from a goal down to book their place in the final of the Derbyshire Senior Cup.
Massiah McDonald cancelled out Jacob Hazel’s opener from the penalty spot before heading home what proved to be the winner midway through the second half.
Hazel, who spent a month on loan at the Reynolds Stadium earlier this year, put a youthful looking Spireites side ahead after he was needlessly brought down in the box by Martin Foster.
The striker dusted himself down and calmly placed the ball into the top left corner on 10 minutes.
Matlock, however, continued to pass the ball around with confidence and James Ashmore, in particular, looked to dictate play at every opportunity.
McDonald came close with a looping header moments before he levelled the scores for the hosts.
Foster made amends for his earlier mistake by delivering an inch-perfect delivery for the front man to run on to. McDonald chested the ball down into his path and slotted past Josh Barrington.
Ashmore tried his luck early in the second half with a dipping volley from the edge of the box which was Barrington comfortably scooped up.
The Gladiators then took the lead when Lee Featherstone’s inviting centre was headed home by McDonald five yards out.
Hazel thought he had scored his second of the night when he nipped in ahead of Jon Kennedy to divert the ball towards goal, only for the covering James Lukic to preserve his side’s lead.
Bradley Grayson should really have added a third for Matlock but the winger got caught in two minds seven yards from goal and was eventually crowded out.
McDonald had a free shot on goal but angled his first time shot wide of Barrington’s left hand post as the match drew to a close.
The second semi-final between Ilkeston and Alfreton will be played on March 19.
Gladiators (4-4-2): Kennedy, Harcourt, Featherstone, Foster, Yates, Lukic, Grayson (Dennis 82), Ashmore, McDonald, Davies, Griffiths-Junior
Subs not used: Hindley, Laight, Travis, Buxton
Spireites (4-4-2): Barrington, Slack (McNicholas 88), Clarke, Scully, Broadhead, Whittaker, Wafula, Hewitt, Bowland (Mason 70), Hazel, Fereday.
Subs not used: Noel, Mathers, Brock
Referee: Mr J Adcock (Long Eaton)