All four missed the Johnstone's Paint Trophy defeat at Northampton in midweek and are rated as doubtful to face the Spireites.
Defender Scott Guyett has undergone knee surgery and is expected be out for a couple of months, while midfielder Mark Molesley had an injection in his foot this week and is expected to miss out.
Sammy Igoe (bruised marrow) is sidelined for two weeks and fellow midfielder Joe Partington (groin) is also unavailable.
Midfielder Marvin Bartley played in the centre of defence against the Cobblers despite having a broken hand and could play at the back once again. To make matters, the Football League reversed their decision to allow boss Eddie Howe to make a second emergency loan signing this week.