For Pompey’s opening game in the competition at Crawley, only Ronan Curtis started the league match against Port Vale three days earlier.
And that type of rotation is expected again as Cowley looks to get minutes into the legs of those who have been on the fringes in recent fixtures.
Several of the club’s academy youngsters could also be called upon to make up the numbers.
So who will the manager be turning to for tonight’s fixture?
Here’s how we think the Blues could line up.
1. Josh Oluwayemi
The former Spurs youngster started the game at Crawley as he got his first taste of Pompey action following his summer move. He continues to play second fiddle to Josh Griffiths but Danny Cowley is keen to see the 'outstanding' form he shows in training on a match day. Tonight he'll be given another chance to prove his quality - only this time in front of the Fratton faithful. Photo: Jason Brown
2. Zak Swanson
The former Arsenal youngster is having to bide his time for first-team opportunities having featured just one in the league this season. That's despite Joe Rafferty missing the past three games through injury and left-back Connor Ogilvie coming over to deputise at right-back. Seen as a 'project' by Cowley, it's these types of games which the manager believes will aid Swanson's development and have him pushing for more game time further down the line. Photo: Jason Brown
3. Kieron Freeman
The former Sheffield United defender's two appearances to date have come in the Papa John's Trophy and Carabao Cup respectively. He's clearly well down the pecking order but the 30-year-old needs some form of match action to maintain his fitness. Is likely to feature tonight, with a role at centre-back a possibility. Photo: Jason Brown
4. Sean Raggett
Danny Cowley is keen to get minutes into some of his fringe players, but with Pompey without a game for two weeks prior to their visit to Ipswich on Saturday, there could be a need to maintain certain players' sharpness. Raggett or Clark Robertson could fall into that category. Meanwhile, their leadership will be needed as Cowley makes wholesale changes to his line-up. Photo: Jason Brown