Dave Kitson has been ruled out of Pompey’s next three matches.
The striker has torn a muscle in his side.
The injury flared up in training the day before the trip to Hull, keeping him out of the 1-0 defeat.
Now Steve Cotterill doesn’t expect the former Reading man to return until after the international break.
That will see Kitson miss tomorrow’s visit of Blackpool.
He will also be absent from the Fratton Park clash with Peterborough on Tuesday night and the trip to Leeds on October 1.
That leaves the Barnsley clash on October 15 as the realistic target for the 31-year-old’s return.
Cotterill said: ‘Kits has torn a muscle.
‘He came back out for training in the early part of the week and we discovered he has a torn muscle in his side.
‘I don’t envisage us having him until after the international break, unless we were very lucky.
‘But I don’t think he will get over that in that period of time.’
Kitson aside, the remainder of Cotterill’s side has been given a clean bill of health.
Luke Varney may be missing through suspension but Liam Lawrence is back following a ban.
Elsewhere, there are no other injury concerns to a squad which is once again likely to include teenager Ryan Williams and towering striker Marko Futacs.
That would put Joel Ward in the frame to operate as one of the midfield three after being restored to the side against Hull.
However, Hermann Hreidarsson is set to miss out on a squad place once again.
Cotterill revealed training had taken on an extra edge this week.
And, fortunately, it hadn’t claimed any casualties.
He added: ‘Training has been rife with tackles this week.
‘They must be the ones we saved up from not using last week.
‘Fortunately, everyone is okay, though.
‘They have trained very well – very competitively.
‘They definitely knew they let probably themselves down, the fans down and me down against Hull last week.
‘They are a top set of lads.
‘I know they weren’t perfect last week.
‘But the good thing about these games is there is another around quickly to put it right.’