Kenny Jackett will continue to use the Checkatrade Trophy to rotate his squad.
Pompey visit fellow League One side Southend on Tuesday evening with a place in the quarter-finals at stake.
And while they enjoyed a dramatic FA Cup victory at Norwich on Saturday, their hosts were afforded a free weekend.
So Jackett is going to make numerous changes at Roots Hall, while still expecting his side to put up a decent fight.
The Blues boss said: “It’s a competition that we’ve done very well in so far and it’s been interesting for me to look at some players who haven’t had much game-time.
“That will be the same again at Southend – we’ll change the team around. There will be a combination of those on the fringe and an opportunity for some young guys.
"It’s quite hard when you’re watching from the sidelines and wanting to get in, but this gives a decent chance for a different set of players."
“We’ve used it very constructively so far and still got results, so we’ll be looking for both again if we can on Tuesday.
“It’s quite hard when you’re watching from the sidelines and wanting to get in, but this gives a decent chance for a different set of players.
“Southend are a very competitive League One team and will be working hard to get themselves up around the play-off places.
“We’ve got through to the knockout stages and if we can keep progressing on all fronts that would be great because there’s the carrot of a Wembley appearance at the end.
“But every win we’ve had in any competition this season has been hard-earned and we know it’s not going to get easier.”
One man who will definitely not be involved is Ben Thompson, with the in-form midfielder being recalled from his loan spell.
Jackett said: “We have said that if we can get him back, we would. It’s obviously Millwall’s call and the ball is totally in their court.
“He’s been a very successful player for us and if they make him available again then we’d be interested.”