A first-round that did not disappoint the fans had continued with more explosive action in the second.
Usman landed a perfect right hand that took the lights off Masvidal with the Nigerian landing five hammer shots to close up the fight.
The knockout came at one minute, two seconds.
The fight is the first UFC card in front of a 15,000 capacity crowd since the COVID-19 pandemic shut down spectator sports in March 2020.
With Sunday’s victory, the Nigerian recorded the second-longest winning streak in UFC history. Earlier, Usman tied with Khabib Nurmagomedov and Jon Jones with 13 straight victories.