Hislop broke a finger in the warm-up on Sunday, but played through the pain barrier - and, a host of great stops and a saved penalty later, helped Pompey to the quarter-finals for the first time in eight years.
However, Hislop is desperate to play against his old club - whom he so nearly won the Premiership with in 1996 - and has said if it is at all possible, he will play.
With Pavel Srnicek, another former Newcastle goalie, on loan at West Ham, Herald Wapennar will deputise if the worst comes to the worst.
On a happier note, Lomana Lua Lua has been cleared to play against the club which holds his registration on Sunday.