Shunji Kosugi made his debut on January 11, 1981. He was known for his technical prowess in the ring, influenced by Karl Gotch. He was the last man to defeat Satoru Sayama, before Sayama became Tiger Mask. He was also the very first opponent of the future Jushin Thunder Liger, Keiichi Yamada.
Kosugi's biggest accomplishment came in April 1985, when he defeated Keiichi Yamada to win the very first Young Lion Cup.
As time went on, Kosugi suffered a severe back injury, which forced him to retire on April 10, 1988. His last recorded match as an active wrestler occurred on March 18, teaming with Don Arakawa, losing to Hiro Saito and Norio Honaga.
After retiring from the ring, he returned to his hometown to run a liquor store, owned by his wife's family.
In September 2010, after over 22 years since his last match, Kosugi made a surprise return in a battle royal, held by Tatsumi Fujinami's Dradition promotion. Although he lost, he received a standing ovation by bodyslamming Kikutaro.
- Finishing and signature moves
- Oklahoma Stampede