"Brooks has less than a 50 per cent chance of facing Crewe, while Enoch is 50-50 at the this stage," Gary Johnson told www.bcfc.co.uk
New loan signing Nick Wright goes into the squad, Louis Carey is back after a ban and Jamie McCombe (foot) is fit.
Crewe boss Dario Gradi has a doubt over David Vaughan (toe), while Billy Jones (hamstring) and Darren Moss (groin) are both set to miss out at Ashton Gate.
Lee Matthews will be sidelined with a knee injury, while Lee Bell (foot) and Tony Grant (Achilles) are not ready.