He was instrumental in founding the Japanese Amateur Wrestling Association and bringing the 1964 Olympics to Japan.

Originally a judo specialist and a secretary to Kanō Jigorō he helped popularize judo in the United States and Europe.

[2] In 1965, Hatta also helped Victor Koga to form the Japanese Sambo Federation.

Tadaaki was a 1965 NCAA champion, two-time All-American, and coached Olympic and world teams for Japan, USA, and Mexico for 50 years starting in 1968.

[3][4] Maasaki was an NCAA championship in 1962, placed second in freestyle at that year's world championships, three-time NCAA All-American, AAU All-American, and later coached Olympic gold medalist Steve Fraser.