The chief trainer of Aoki Masaru, Kimura Tatsuya, and Itagaki Manabu, Shinoda carries out Coach Kamogawa's tradition of strict training. Aoki and Kimura have even referred to him as "The mud-fighter producing trainer from hell."

Though arguably the least prominent of the main characters, he is shown to still have a good boxer's eye. He is the creator of the inspirational pun Gattsu de Gattsun Gattsun da!