It depends how highly you value defences of fractured and/or non-linear titles. Most of Calzaghe's defences were of the less prestigious WBO belt only. Parallel to him, Ottke was also making a lot of defences at super-mid with the IBF and WBA. Same goes for Hopkins and Holmes, who held only the IBF and WBC titles respectively for much of their reigns. Even Jones never technically held a linear title, his WBA and IBF titles having been stripped from Dariusz.
So I personally would give Calzaghe a middle-ranking, with only the likes of Louis, Hagler and Monzon, who were defending the linear universally recognised title, in the top echelon.
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