The heavyweight main event pits Romero against Alex Nicholson at Unrivaled Arena in Miami, with free YouTube prelims from 7 p.m. ET and the main card at 9 p.m.
Romero, 48, was initially due to face Hector Lombard and is making his first bareknuckle MMA appearance after competing across PFL, BKFC and other combat promotions since 2024.
The card, promoted by Jorge Masvidal's Gamebred organisation, also features Marcos Rogerio de Lima, Tim Johnson and Ultimate Fighter 31 winner Kurt Holobaugh in former UFC-heavy matchups.
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