Featherweight world champion Amanda Serrano stopped Stevie Morgan 38 seconds into round two in their light-welterweight contest in Florida.

Puerto Rican Serrano was due to fight Ireland’s undisputed world lightweight champion Katie Taylor to headline an event featuring a bout between YouTuber-turned-boxer Jake Paul and 58-year-old former heavyweight champion Mike Tyson.

Tyson withdrew on medical grounds in May and both fights were postponed until 15 November.

Instead, Serrano outclassed fellow 35-year-old Morgan, from the US, at the Amalie Arena in Tampa.

The referee stepped in after Serrano landed a flurry of punches in the second of the eight two-minute rounds, claiming her first stoppage victory in three years.

In the co-main event, 27-year-old Paul stopped fellow American Mike Perry in the sixth round.

Perry, 32, left the UFC in 2021 and has become one of the most recognisable faces in the emerging bare-knuckle fighting scene in the US.

Paul floored Perry with an overhand right inside the first minute of the fight and again with a powerful right early in the second.

The bout was stopped midway through the sixth of the eight rounds as Perry – his face bloodied and swollen – stumbled after climbing off the canvas once more.