Wigan will arrive at Fratton Park sitting on top of the League One table as they battle for the title.
But the Blues have their own promotion hopes to worry about ahead of the televised Easter Monday contest.
Saturday’s 1-0 victory at Walsall means they sit two points outside the play-off places with seven games remaining.
Anton Walkes is not thinking about that yet, though, and just wants Pompey to produce a positive performance against the Latics.
The loanee said: “It’s too early for us to be looking at the play-offs, so we’ll continue to take it one game at a time.
“The run we’re on means that we can be pretty confident and focus on positives rather than negatives, although there are still areas where we can improve.
"It’s too early for us to be looking at the play-offs, so we’ll continue to take it one game at a time."
“We’ve kept three successive clean sheets and that’s as good as a hat-trick for me as a defensive player because it gives you something to build on.
“Wigan are a great team and are probably favourites to finish top of the table, so it’s a game you have to look forward to.
“But we’ve got to show them what we’re about, especially because the fans will be getting behind us as usual.”
Walkes had been used exclusively as a right-back after arriving from Tottenham in January, but was handed a holding midfield role at Walsall.
“I didn’t mind it,” he said. “It was all about trying to keep their creative players quiet and I felt I did that.
“We were able to get to those second balls and we kept a clean sheet, which was the most important thing.
“I don’t mind where I play. I just want to be out on the pitch and every time I step out there, I try to enjoy it. I’m up for any challenge.”