WARNING: The images below may be graphic to some.
Said's leg bent awkwardly as he tried to land, the sound of the injury echoing through the arena.
Said writhed on the ground in agony while medical officials tended to him. He exited on a stretcher to a standing ovation.
The injury came minutes after Germany's Andreas Toba hurt his knee during floor exercise. Toba abandoned his routine and was helped off by trainers but managed to compete on pommel horse before exiting to receive medical attention.
The U.S. men are leading halfway through the second subdivision thanks to a strong performance from four-time national champion Sam Mikulak. Great Britain, which took third at last year's world championships, is second. The top eight teams in qualifying will move on to Monday night's team final.