Royama rose to some notoriety when at the age of 25 he became champion of Kyokushin's 5th All Japan Tournament, and later when he defeated the American, Charles Martin, a giant who stood nearly a foot taller (about 30 cm) than himself, in the 1st World Open Karate Tournament in 1975. This young prodigy of Mas Oyama then went on to a historic finish in that 1st World Open Tournament, when a split-decision was finally broken by the tournament judges in the final match and 1st place was given to Katsuaki Sato, leaving Royama with no choice but to accept 2nd place. The day following the tournament when more than a few fighters entered the hospital for injuries sustained during the competition, Royama attended his usual training. No one who knows Kyokushin Karate today can hardly separate the style from its devastatingly powerful low shin kick. Not everyone knows, however, that it was Royama who made this technique famous. At the early World Tournaments the Japanese would hear the foreigners yell, "Low kick! Low kick!," and since the pronunciation of "R" in Japanese is so similar to "L", it was an honest mistake for them to hear "Ro kick! Ro kick!" instead, believing that even the foreigners had named this technique after the first Japanese fighter to make it famous. After all, it was with Royama that all of Japan had associated the introduction of this bone-breaking technique ever since they'd watched Royama break down Charles Martin in the 1st World Tournament with one destructive low shin kick after another.