Peterborough boss Gary Johnson will hand a debut to Lewin Nyatanga for the trip to face strugglers Walsall.
Nyatanga has been drafted in on loan from Johnson`s former side Bristol City in the wake of Saturday`s damaging 3-0 home defeat at the hands of runaway leaders Brighton.
The centre-half is likely to start which will mean one of record signing Ryan Bennett or Kelvin Langmead will make way.
At the other end of the field Posh will be without playmaker George Boyd, who starts a three-match ban after seeing red against the Seagulls.
Wide man Tommy Rowe picked up a groin injury at Brentford two weeks ago and is ruled out but forward Lee Tomlin is back from suspension.