Pompey boss Steve Cotterill hopes to have senior keeper Jamie Ashdown signed for the trip to the Ricoh Arena on Saturday but under the terms of Portsmouth's administration, all signings must be ratified by the Football League.
In a complex High Court case, the South Coast based club are appealing about the amount of money that the HM Revenue & Customs are claiming is owed with HMRC's figures being reported as £13m more than Portsmouth's £24m.
HMRC is also disputing as to why other clubs and players owed money should get 100% of monies owed when other non-football creditors are likely to get a lot smaller cut and is objecting them coming out of administration via a Company Voluntary Agreement (CVA).
However, if HMRC win the case and Portsmouth are liquidated, they will lose the £6m offered under the terms of the CVA or if HMRC win and Portsmouth exit administration without agreeing a CVA, they could be docked 15-20 points by the Football League.
Richard Sheldon QC representing Portsmouth is quoted by the BBC as saying: "We see no reason why HMRC want to pursue this appeal. They'd be shooting themselves, other creditors and the fans in the foot. I ask them to go away and consider whether they want to pursue this."