"Fenners had a scan on his calf - it's the other leg this time and that will keep him out for 2-4 weeks", Moore told Radio Sheffield's Football Heaven.
"Exy's loan is up and Dean Holden also goes back, I've got John Mullins who can fill in there but I want some experience, it's just a case of managers saying 'yes, lets do a deal and we're willing to let you have someone for a month', I've got young Luke (Ashworth) but I want some experienced cover.
"Posh want 100 grand for Exodus so I can't see anything happening there."
Meanwhile Moore ruled out messageboard chat linking him with Nicky Wroe, who has been transfer listed at Torquay.
"They are looking at near enough 100 grand or maybe a part-ex, which is out of our range at the moment - I want a sitter who can go in there and pass it, and he's more of a box to box lad who'll get you goals but we'll sit tight on that just at the moment.
"We're going to give Bradders a chance to do that at the weekend and we've been working on him sitting and getting a range of passing going to set us on the attack - his passing in training has been magnificent to be fair", added Moore.