A shy young man, he was Nisei (second generation) born on June 24, 1925, in Olowalu, Maui, where his father Matsusai, an Okinawan, had moved to find work in the sugar cane fields. He is considered one of the greatest athletes to come out of Hawaii.
In 1947, Yonamine signed with the San Francisco 49ers, He was the first Asian-American to play professional football; but his football career was cut short after fracturing his wrist. Later, Wally Yonamine found himself the starting center fielder of Japan’s Yomiuri Giants. In 1957 he received the MVP award; he was inducted into the Japanese Baseball Hall of Fame in 1994.