Jayden Stockley has been ruled out of Pompey’s trip to Cambridge United.
The striker has spent the week receiving treatment at parent club AFC Bournemouth after injuring his ankle during the goalless draw with Yeovil Town.
With Adam McGurk still missing with his ankle injury, it leaves Matt Tubbs and Conor Chaplin as the Blues’ strike options at the Abbey Stadium.
The time frame for Stockley being sidelined is unclear at present after the target man returned to the Cherries.
Although, he is definitely missing from Paul Cook’s plans for Pompey’s fixture with the 19th-placed side.
Cook said: ‘Jayden has an ankle problem and Bournemouth have taken that over now.
‘We will know more after the weekend but he won’t be involved at all against Cambridge.
‘I am not sure the full extent of it but it has come from the game on Saturday against Yeovil.
‘McGurk is getting nearer to returning, I would imagine he’ll be back in another couple of weeks.’
Brian Murphy, however, could make a return to the Blues’ squad for the clash with Richard Money’s team.
The 32-year-old returned to training on Tuesday and has so far come through with no reaction to his groin problem.
Cook insists Aaron McCarey will definitely start against the U’s, marking his third successive appearance.
However, he admitted Murphy could come in on the bench to serve as the substitute keeper in place of Alex Bass.
That would allow the youngster to line up for the Academy in their home fixture with Yeovil at Furze Lane on Saturday (11am).
He added: ‘Murphy is training and looks like he could be back involved.
‘We will see how he reacts from today’s training.
‘I would imagine once the Cambridge game has gone he can be considered for playing in the first team.
‘That will be irrespective of whether he will be sub on Saturday.
‘But he won’t be in contention to play in the starting XI at Cambridge.’
Paul Jones (knee ligament) and Michael Poke (collarbone) both remain on the sidelines for Pompey as they continue their injury rehabilitation.
McCarey joined Pompey on a 28-day loan from Wolverhampton Wanderers at the end of last month to ease their goalkeeping crisis.
Murphy has missed the last four matches.