If O'Riordan is recalled, then we currently have 0 spare slots. In fact, we also have to factor in Garrett (who returned from injury recently) & Barrett (whose loan ends in January).
Although I wouldn't expect either of Garrett or Barrett to be in the 25, we could well have 27 players who need to be considered (be that selling/loaning out etc) before we think about bringing more in
Toth, Pears, Barrett
Wharton, Carter, Miller, McLoughlin, Pratt, O'Riordan
Hedges, Pickering, De Neve, Ribeiro
Alebiosu
Cantwell, Tronstad, Morishita, Baradji, Gardner-Hickman, Henriksson, Forshaw, Tavares, Garrett
Ohashi, Gudjohnsen, Gueye, Kargbo
* anyone not mentioned above (Montgomery, Litherland etc) is young enough not to be included in the 25