With Boogs game having signicantly deteriorated and the other two CB's being very young I think it would have to be the likes of Baro or someone similar from overseas (Like the Dutch fella at Sydney FC) or if Aussie then Spiranovic is the only experienced Aussie CB that I could think of other than maybe Curtis Good on loan to rebuild his career but he still isn;t that experienced. Whilst I don't mind Tratt as a player he is not what we need right now.