Tranmere boss Les Parry admits injured playmaker Andy Robinson could prove difficult to replace.
Robinson is facing a month on the sidelines due to a hamstring strain sustained during last Tuesday's win over Port Vale in the Johnstone's Paint Trophy first round.
Parry is now seeking to bring in a replacement on loan, but acknowledged few players operate in the free role that Robinson often occupies.
Parry said: "Not many teams play with someone in that position, the hole.
"I think players like the idea of the freedom the role gives them because generally they are not given any specific marking to do.
"I'm in no doubt that lots of players want to play there but I'm not sure whether there are that many who have actually done it."