Zakuani returned to the starting line-up against Watford last weekend after a three-game lay-off with his troublesome groin injury but is not yet fully fit.
Manager Mark Cooper will monitor the fitness of Zakuani closer to kick-off, with Craig Morgan set to fill in if required.
Cooper – who tasted victory in the Football League for the first time against the Hornets – has no other injury concerns and will continue to select Aaron Mclean despite the striker handing in a transfer request last week.
Mclean and strike partner Craig Mackail-Smith have scored 15 times between them this season and will line up once again as Posh look for their first win at the Hawthorns since a League Cup win in 1988.
Defender Danny Blanchett has returned after spending the maximum 93-day period with Hereford but is unlikely to feature.