The reserves won 3-1 at Scunthorpe United on Tuesday afternoon in their opening Final Third Development League Cup group match.Rai Simons scored twice after the Spireites took an early lead with an own goal.
The opening goal came in only the fifth minute when Scott Wiseman headed into his own net from a Dion Donohue free-kick.
Aaron Chapman saved from Kyle Wootton as the hosts looked for an instant reply.
Simons extended Chesterfield's lead in the 22nd minute when he found the net with a header following good work from Jake Orrell.
Chapman came to Chesterfield's rescue again, producing a fine save to keep out Sean McAllister's volley.
Simons scored his second of the match in the 27th minute, cutting inside and finding the net with a curling effort.
Byron Harrison fired over before Scunthorpe pulled a goal back through Dave Syers in the 51st minute.
Simons went close to sealing his hat-trick, heading narrowly wide from a Ritchie Humphreys cross.
Harrison had to go off after picking up a knock and he was replaced by young Derek Daly.
Chesterfield line-up: Chapman, Maguire, Humphreys, Onovwigun, Donohue, Simons, Beesley, Gnanduillet, Orrell, Triallist (Milner 89), Harrison (Daly 68). Unused subs: Parkin, Hudson, German.