In the 27-year history of the UFC, only seven fighters have won championships in multiple weight classes -- and only four of those have held both titles simultaneously.
Such is the rare air UFC middleweight champion Israel Adesanya (20-0) is hoping to reach Saturday, when he challenges Jan Blachowicz (27-8) for the light heavyweight title at UFC 259. The Nigerian-born, New Zealand-based star will look to become the UFC's next ''champ-champ,'' a term used by Conor McGregor in 2016 when he became the first to hold two belts at the same time.