Former Blues boss Steve Cotterill lies in waits with five games of the League One season remaining.
His side had won their five past home games on the spin, before defeat to Peterborough last time out.
So a tough test lies in wait for John Mousinho’s side, with play-off hopes receding going into the game.
Pompey have fitness and suspension issues to consider going into the game – so this is how we think they will line up at New Meadow.
13. SUB: Di'Shon Bernard
Showed his potential at MK Dons and was back on the bench on Monday. Pushing hard for inclusion. Photo: Jason Brown
14. SUB: Denver Hume
Would be harsh on the former Sunderland man to miss out after a decent showing against Morecambe, but the stronger defensive instincts of Ogilvie could be favoured. Photo: Graham Hunt
15. SUB - Louis Thompson
Not started the past two, but will be in John Mousinho's thoughts - especially against opposition with strong home form. Photo: Jason Brown
16. SUB - Michael Jacobs
Nip and tucker whether the attacking talent makes it after missing Monday with a tight calf. Photo: Jason Brown