The Nigerian-born Texan stopped Gilbert Burns with punches 34 seconds in the third round at UFC 258, taking his record to 18-1,
Defending his title for the third time, and breaking Georges St Pierre’s consecutive welterweight victories record in the process.
Usman was put down in the first round, but recovered impressively to stop Burns early in the third.
In the night’s other main bout, Mexican flyweight Alexa Grasso beat Maycee Barber by unanimous decision after a hard-fought contest.
Four of the nine fights were decided by unanimous decision, with Kelvin Gastelum beating Ian Heinisch, Ricky Simon defeating Brian Kelleher, Belal Muhammad overcoming Dhiego Lima, and Christ Gutierrez outdoing Andre Ewell.