Portsmouth are without loan duo Mikkel Andersen and Scott Allan for their FA Cup tie with Notts County.
Goalkeeper Andersen has made 16 appearances this season but has been denied permission to play by parent club Reading.
Midfielder Allan made his Pompey debut on Monday against Sheffield United, but his club West Brom will not let him make his home bow at Fratton Park.
Boss Michael Appleton also expects fellow loanee Carl Dickinson to be unavailable for the 2008 winners, but is still waiting on confirmation from Watford.
Forward Ashley Harris is struggling with an ankle injury and is a major doubt, while midfielder Darel Russell remains sidelined with a hamstring injury.
Appleton's attempts to bring in a striker ahead of the game were scuppered as Sheffield Wednesday striker Chris Maguire suffered a knee injury and was unable to complete a loan move.
Notts County boss Keith Curle expects to have an unchanged squad.
Goalkeeper Fabian Spiess (knee), defenders Julian Kelly (hamstring), Tom Williams (calf), Carl Regan (ankle) and Manny Smith (knee) and midfielder Joss Labadie (knee) all remain unavailable but are closing in on a return to contention.
``They are all coming back into the fold now,'' said Curle.
``Within two or three weeks we will have nearly a full complement of players back which, going into the Christmas period, is great because we are going to need every single one of them.''
With so many defenders absent, it means midfielder Gary Liddle is likely to continue to fill in at right-back at Fratton Park on Saturday.