Harrison Maurus broke the under-77 kilograms world record on another day of American success at the International Weightlifting Federation (IWF) Youth World Championships in Thai capital Bangkok.
It followed the world record breaking exploits of his team-mate Clarence Cummings Jr yesterday in the under-69kg division
Maurus lifted 140kg in the opening snatch event to place second behind Russian Aleksandr Urvachev, who managed 142kg.
But the American proved a class apart in the decisive clean and jerk.
He produced three successful lifts culminating in a majestic 192kg with his final effort.
This added a single kilogram to the youth world record previously held by Yeison Lopez of Colombia.
Urvachev proved unable to come close, but still took silver with a combined total of 312kg.
Asslyzhan Bektay of Kazakhstan clinched bronze with 306kg.
Fang Lin of China proved far strong for the rest of the field in the women's under-63kg event.
She managed a 93kg snatch followed by a 117kg clean and jerk for a total of 210kg.
Darya Pavlova of Kazakhstan lifted a combined 201kg to finish second.
China also took bronze courtesy of Jiang Yunliu, who lifted 199kg.
Action is set to continue tomorrow in Bangkok.