A fictional character created by Sega to advertise the Sega Saturn in Japan between 1997 and 1998. He is a parody of Sugata Sanshirō, a legendary judo fighter from an Akira Kurosawa film.
Sanshiro is a dan holder for multiple Japanese martial arts (karate and iaidou first dan, judo third dan, battoudou fourth dan, toudou 7th dan, etc). He is portrayed by actor Fujioka Hiroshi, who, until that point, was best known for playing the hero Takeshi Hongo in the influential tokusatsu superhero series Kamen Rider.
For Sega's 60th anniversary, in late March 2020, a new mascot was revealed, one who was Segata's son, called Sega Shirō (せが四郎), actually played by Fujioka Hiroshi's eldest son, Fujioka Maito.