I don't get why people are saying we don't need anymore defenders?
Sure we have numbers, but none of them are truly class or have bags of experience. Jones and Smalling are almost there, but not quite. Evans is there. Blackett and Keane though are nowhere near being PL winning centre backs, and Rojo is probably on a par with Jones and Smalling in terms of experience as he hasn't played PL but has played first team football for a while.
Also this ignores the key fact that, Jones, Smalling, and Evans have been highly susceptible to injuries. Could you count on those 3 being fit for a season? Not a chance in hell.
Having 6 defenders is irrelevent if 1 has no PL experience, 2 are far too young to be considered real options, and 3 who are good enough but injury prone.