Danny Cowley will give some of the younger members of his squad the chance to impress at Cardiff.
Pompey visit south Wales to face the Championship side this evening in the first round of the Carabao Cup.
The hosts are also likely to make changes from the side that were beaten at Reading in the league at the weekend.
But Cowley does not want to start second guessing his City counterpart Steve Morison and is more concerned with how his men fare.
The Blues boss said: “They’re a Championship side who have recruited aggressively over the summer and have a real depth to their squad.
“There are a lot of options for them all over the pitch and these are always difficult games to prepare for because you’re never quite sure what the opposition will do.
"We have got some young players who will really benefit from the chance to take on a Championship team."
“We don’t know what they will do in terms of their side, but the focus up until the game starts will be on what we do.
“There will certainly be some changes for us on Tuesday because that’s the right thing for us as a group.
“We have got some young players who will really benefit from the chance to take on a Championship team.
“There are 10 players aged 21 or under in our group now, which is fantastic for the future of this club, and now we really need to develop them.
“We’re working very hard with them on the training pitch, but we all know that the game time is crucial.
“Some will play at Cardiff and that will help us make a decision on what we do next, whether they stay with us or we let them go out on loan.
“These are the kind of challenges that young players really need if they are going to develop and grow.”