Not only the organization's co-founder and most popular fighter, Funaki was also one of Pancrase's most successful fighters to date, scoring submission victories over numerous MMA champions such as Ken Shamrock, Frank Shamrock, Semmy Schilt, Guy Mezger, Yuki Kondo, Minoru Suzuki, and Bas Rutten through the course of his Pancrase career. He is the only fighter in mixed martial arts to hold wins over both Shamrock brothers and Bas Rutten, and was the first man to win the King of Pancrase title twice.