Peterborough will be without striker Dave Hibbert for the tricky trip to Southampton.
Hibbert dislocated his knee after coming off the bench during the 4-1 FA Cup replay win over Stockport on Tuesday night and is set for several months on the sidelines.
Full-back Nana Ofori-Twumasi is out with a groin injury, while former Stockport winger Tommy Rowe is also sidelined with a groin strain.
Midfielders Charlie Lee and Chris Whelpdale joined Gillingham on loan last week so are absent, but on-loan defensive duo Lewin Nyatanga and Marcus Williams return after they were ineligible to face the Hatters in midweek.
Midfielder Lee Frecklington rounds out the absentees after he suffered ankle ligament damage.