|Birth name||Seiji Sakaguchi|
|Born||February 17, 1942|
Kurume, Fukuoka, Japan
|Professional wrestling career|
|Ring name(s)||Big Saka|
|Billed height||196 cm (6 ft 5 in)|
|Billed weight||125 kg (276 lb)|
|Billed from||Tokyo, Japan|
|Trained by||Karl Gotch|
|Debut||5 August 1967|
|Retired||15 March 1990|
|Men's Black Belt Judo|
|1965 Rio de Janeiro||+80 kg|
Seiji Sakaguchi (坂口征二, Sakaguchi Seiji, born February 17, 1942) is a Japanese retired professional wrestler and judoka, Sakaguchi holds a 7th dan red and white belt in Judo. Sakaguchi was a mainstay of New Japan Pro-Wrestling (NJPW) and also competed for the World Wide Wrestling Federation and the National Wrestling Alliance. His sons are professional wrestler and mixed martial arts fighter Yukio Sakaguchi and television actor Kenji Sakaguchi. Sakaguchi currently works for New Japan as an advisor.
Before becoming a professional wrestler, Sakaguchi was a judoka with a fifth degree black belt and won the 1965 All Japan Judo Championship. Coach Koji Sone was accused by Anton Geesink's teammates in the 1965 World Judo Championships of having Sakaguchi throw the match against the more rested Matsunaga in order to allow Matsunaga take on the weary Geesink in the final round.
Sakaguchi debuted in August 1967 for the Japan Wrestling Association. When JWA closed down in 1973, he joined New Japan Pro-Wrestling. He retired from the ring in March 1990. He was the president of the National Wrestling Alliance from 1992 to 1993.
At age 61, Seiji Sakaguchi came out of retirement to team up with Masahiro Chono against Yoshihiro Takayama and Shinya Makabe on September 14, 2003.
Sakaguchi appeared in the 1982 American film Forced Vengeance. His role was a minor one, though he did appear in the film's climactic fight scene, battling star Chuck Norris.