American Jermell Charlo has become the first-ever undisputed super welterweight champion after beating Brian Castano via a 10th-round technical knockout.

The 31-year-old floored Castano twice in the 10th round.

This means Charlo is now the holder of the WBA, WBC, IBF, and WBO titles.

The four belt unification bout lived up to expectations after battling to a draw in their first meeting last July.

Charlo brought his WBA, WBC and IBF championships to the ring at Dignity Health Sports Park in Carson, California while Castano put his WBO title on the line.

The first meeting between the pair was one of the better fights of 2021, going the full 12 rounds before judges scored the fight 117-111 Charlo, 114-113 Castano, and 114-114 even.

Five days before his 32nd birthday, Charlo’s 19th knockout made him the seventh undisputed male champion in the four-belt era, and the first at this weight, while Castano’s defeat was the first of his career.