There will be no permanent switch to a 3-5-2 system for Paul Cook tomorrow night.
The formation change helped the Blues to a late 3-0 victory over Carlisle at the weekend.
But Pompey’s boss has ruled out ditching his preferred 4-2-3-1 from the start. That means the hosts could be unchanged from the team who lined up for the Brunton Park trip.
Certainly, with no fresh injury concerns, Cook possesses the option to go again with the same side.
Elsewhere, he may again choose to rotate Carlisle scorer Jack Whatmough with Tom Davies on the bench.
Meanwhile, Peter Murphy is expected to return to Morecambe’s starting line-up for their visit to Fratton Park.
The Shrimps’ skipper has sat out the past three matches following a red card at Barnet earlier this month.
It was a period which reaped two wins and a draw for Jim Bentley’s in-form side.
However, the midfielder is likely to replace Anthony Evans.
Evans, who featured for 70 minutes in last weekend’s 1-0 victory over Grimsby, will drop to the bench, replacing Ben Hedley.