Kenny Jackett is facing an injury crisis in the wake of a depressing defeat to Oldham Athletic.
Pompey’s defensive options have been decimated after the 2-1 loss on Saturday, marred by crowd disturbances and disorder around Fratton Park.
And top scorer Brett Pitman is dealing with an ongoing knee problem as he undergoes an operation on his broken nose this week.
Key defender Christian Burgess is facing up to a fortnight out with a calf injury, while Nathan Thompson was left concussed after an aerial clash with team-mate Drew Talbot against the Latics.
Left-back Damien McCrory is out for up to six weeks as he undergoes a knee operation on Wednesday.
On top of that, Jack Whatmough and Tareiq Holmes-Dennis are both out long term with knee injuries.
It leaves Matt Clarke as the only fit first-team central defender available.
Full-backs Brandon Haunstrup and Talbot are the other healthy defenders, along with versatile pair Gareth Evans and Dion Donohue.
Jackett is now considering calling on untried academy youngster Matt Casey, while Oli Hawkins was used as a makeshift defender against Oldham.
The Pompey boss said: ‘The problem is the whole back four.
‘It is quite a long list in a unit you want to settle. We want to give our attacking play a chance to find rhythm.
‘McCrory will have an operation on his cartilage on Wednesday.
‘He’s damaged the meniscus and the estimation is he’ll be out four-to-six weeks.
‘It’s gone from Holmes-Dennis to having two left-backs having operations.
‘Donohue has come as a midfielder but has played left-back and not played badly either.
‘There are injuries right across the back line which has disrupted us.
‘Burgess has a calf injury from Tuesday. He’ll be missing for somewhere along the line of 10 to 14 days.
‘Nathan is concussed. It was a communication mistake between the two players but these things happen.
‘It’s a complete accident and he’s stretchered off with concussion.
‘Hopefully he will be okay but we’ll see the extent of it.
‘(Apart from Clarke) there isn’t a recognised centre-half on the books.
‘We had to switch Hawkins and he showed a great attitude. I don’t know if that will happen again now.
‘We have one under-18 player – Matt Casey.
‘We’ll have to see how he is and how he’s performed. But he’s the next one in.’
Pitman will miss tomorrow’s Checkatrade Trophy tie with Crawley as he undergoes a nose operation – but he also has a knee problem.
Jackett added: ‘Brett wants to stay on and score a goal but he has a problem with his nose and slight problem with his knee. He has some floating bone there.
‘At least we have a break until next Sunday.’