Complex sentence: Upon discharge from the military in 1948, he witnessed his first physique contest; the inaugural NABBA Mr. Universe contest, in which John Grimek edged out Steve Reeves in controversial fashion.
Split into simpler sentences: Upon discharge from the military in 1948, he saw his very first physique contest. This was the inaugural NABBA Mr. Universe contest, in which John Grimek edged out over Steve Reeves in controversial fashion.