Andre Green will miss Pompey’s top-of-the-table clash with Peterborough.
The on-loan Aston Villa winger, who was withdrawn 45 minutes into his debut against Shrewbury last Saturday, sits out the trip to London Road with a knee injury.
He joins Anton Walkes (groin) and Jack Whatmough (hamstring) on the sidelines, with both defenders expected to be fit for the visit of Wycombe on September 22.
Also ruled out of the Posh trip is Dion Donohue.
He picked up a hamstring injury when playing for the reserves against Reading in midweek.
The former Chesterfield utility man is yet to appear for the Blues this season, after suffering from glandular fever in the summer.
Speaking ahead of the Peterborough game, manager Kenny Jackett said: ‘Anton Walkes and Jack Whamough will be absent at the weekend but should be fit for next week.
'Added to that, Donohue has a very tight hamstring which he did against Reading in the week which is frustrating for him - some niggly injuries after his illness that just mounted up.
Nothing serious, though. With the majority of the season ahead, he should be able to make a very good contribution.
'Meanwhile, Andre Green has a knee problem that will keep him out this weekend.’
Ronan Curtis returns to the Blues’ squad following his return from Republic of Ireland international duty.
Have you read?