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.
9. RW Matt Ritchie
Would be a case to give Ritchie a rest given his high-intensity performances at the age of 35, but Pompey don't have that luxury at present. | National World
10. CAM Callum Lang
Won the penalty and got his first goal in seven on Wednesday night. Whether he can go to the well again for a full 90 minutes is questionable. Photo: Jason Brown
11. Left-wing - Josh Murphy
Like the other attackers, there's has to be a concern about fatigues for Murphy, but has to start with lack of options. | National World
12. CF Colby Bishop
Has to be Pompey's most important player, as he leads the line week in, week out. Another textbook number nine display against Stoke. Photo: Jason Brown