Cox, who was originally expected to be sidelined for a minimum of two months with ankle ligament damage, could make his comeback just three weeks later at the Amex Stadium.
The former West Brom striker is likely to settle for a place on the bench, though, with Dexter Blackstock and Billy Sharp set to continue in attack.
Defender Daniel Ayala was only named among the substitutes for last weekend's win over Burnley after failing to shake off a bout of illness and could now return to the starting line-up.
Fellow defender Greg Halford (calf) and midfielder Jermaine Jenas (calf) are both expected to miss out again.
