Tsuyoshi Kohsaka

Tsuyoshi Kosaka (Japanese: 高阪 剛, Kōsaka Tsuyoshi, born March 6, 1970) is a retired Japanese mixed martial artist, submission grappler and professional wrestler who competed in the Heavyweight division. A professional MMA competitor from 1994 till 2022, he has competed for the UFC, PRIDE Fighting Championships, RIZIN, RINGS, Pancrase, and DEEP. Kosaka is the former King of Pancrase Super Heavyweight Champion.

Kosaka is considered to be one of the early pioneers of mixed martial arts and was one of the top ranked Japanese fighters for several years. Known for his grappling skills, Kosaka is trained in Judo and Shoot Wrestling, His "TK guard" position, a precursor to modern butterfly guard, is famous for its efficiency; former UFC champions Frank Shamrock and Maurice Smith have both credited him with having vastly improved their grappling from that particular position.