Cathcart suffered a recurrence of a back injury in the win over West Brom on Monday.
Back out: Catchcart (left) is likely to miss out against Everton
Manager Ian Holloway has already addressed the problem by withdrawing Dekel Keinan and Rob Edwards from a reserve game in midweek.
Team (from): Gilks, Kingson, Keinan, Edwards, Eardley, Taylor-Fletcher, Crainey, Evatt, Adam, Vaughan, Varney, Ormerod, Campbell, Grandin, Harewood, Southern, Carney, Cathcart, Basham, Euell, Sylvestre, Demontagnac, Phillips.
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