The Blues will aim to build on their performance of high intensity against Stoke on Wednesday, but how Mousinho goes about cajoling another showing from his squad is a big consideration.
With his squad short on depth in terms of quality, the Blues boss has to decide how he can keep his team fresh but also competitive.
Here’s how we think he will go as Pompey aim to cement their place clear of the bottom three at The Hawthorns.
5. CB Ryley Towler
Was really surprising to see Atkinson complete full 90 against Stoke, which suggests Mousinho is planning to give him a rest this weekend as loanee builds return from serious knee injury. Photo: Jason Brown
6. LB Connor Ogilvie
Season continues to go in the right direction - just as well as he's the only orthodox left-back option! | National World
7. CM Andre Dozzell
Isaac Hayden has started the past two games after no senior football before Fratton arrival, so could be time to freshen it up with Dozzell - who could feel hard done by not to start with form decent. Photo: Jason Brown
8. CM Freddie Potts
He's ours for the season! The news the recall date has passed for West Ham to take back the midfielder was music to the ears of Pompey fans, with Potts again putting in decent shift against Stoke. | Jason Brown/ProSportsImages