Ryan Fulton remains a doubt for Pompey’s crucial clash with Plymouth Argyle on Saturday.
The on-loan goalkeeper is struggling with a thigh injury he collected while warming-up before kick-off against Carlisle United.
The complaint forced him out of the reckoning for last weekend’s trip to Dagenham & Redbridge.
Instead, Brian Murphy returned to the Blues squad having himself recovered from injury.
The former QPR stopper took Fulton’s place on the bench in the 4-1 victory over the Daggers last weekend.
However, irrespective of the availability of either Fulton and Murphy, Paul Jones is presently Pompey’s preferred choice in goal.
The 29-year-old has conceded once in three outings since returning from Crawley and regaining his starting spot.
Until a call-up to the Scotland under-21s, Liverpool’s Fulton had impressed during 13 successive matches for Cook’s side.
Yet his thigh problem is not considered too serious and he should be available once more next week.
In the meantime, Pompey are well off for keepers, with Jones, Murphy, Alex Bass and Darryl Flahavan yesterday working with goalkeeping coach Scott Bevan.
Flahavan is training with the Blues while he seeks a new club following his exit from Crawley in January.
The highly-regarded Bass has been a regular presence on Pompey’s bench this season, although still has to make an appearance.
As for Murphy, he has made 22 appearances following his arrival in the summer and is out of contract at the end of the season.
Jones is tied to Fratton Park until the summer of 2017.