Hamann believes Stones will do better next season with better support.
He told the Mirror: “Stones is a capable defender but he simply didn’t have enough support last season, and in the end it was problems in defence that cost City.
“Those problems were coming for a while and should have been addressed.
“(Pep) Guardiola inherited an old, unbalanced squad with an ageing defence where all the full-backs were the wrong side of 30.
“The squad was very poorly put together before Pep arrived, and given City’s resources that was staggering really.”