Pompey are optimistic Kyle Bennett and Kal Naismith will make a weekend return.
The influential attacking pair missed last weekend’s 3-0 defeat at Stevenage.
Bennett (ankle) and Naismith (hamstring) were sidelined by injuries, forcing Cook to change a team on a three-match winning streak.
However, the Blues are eyeing the duo for a comeback in Saturday’s visit of struggling Newport County.
Bennett is responding well to treatment on his turned ankle, although has to return to full training.
Meanwhile, Naismith’s hamstring is believed to be strained rather than torn, which represents encouraging news.
The issue has been put down to fatigue following a hectic recent fixture list for Pompey.
Although the pair are not certainties to be ready for Saturday, the club are presently upbeat.
Bennett had netted in three successive matches before hobbling off in the first half against Grimsby, having turned his ankle.
The in-form winger had earlier that day passed a fitness test on a thigh problem unconnected with the injury which followed.
Naismith was forced off in the second half – 21 minutes after scoring his team’s fourth and final goal in the emphatic victory.
The Scot sustained the problem while producing a moment of skill on the South Stand touchline.
Straight away he indicated to the bench he had to come off – an issue which then ruled him out of the Lamex Stadium trip.
In their absence, Paul Cook opted to line-up with a 3-5-2 at Stevenage, with Tom Davies and Noel Hunt coming into he side.
Saturday’s opposition, Newport, are currently second from bottom.