Frank Shamrock is the adopted younger brother of Ken Shamrock and he is a legend of the sport like his brother. He is the former WEC light-heavyweight (205lbs.), UFC middleweight (195lbs.), and Strikeforce middleweight (185lbs.) champion. He retired in the cage at Strikeforce: Fedor vs. Werdum.
- Frank Shamrock vs. Kiyoshi Tamura - The two men fought to a draw.
- Frank Shamrock vs. Bryan Pardoe - The fight was for the first-ever WEC light-heavyweight title and Shamrock vacated it shortly afterwards to fight for Strikeforce. The fight, in 2003, was Shamrock's first since 1999. Bryan Pardoe had a signifigant height advantage.
- Frank Shamrock vs. Cesar Gracie - The fight was Cesar Gracie's MMA debut and his only fight in his career thus far.
- Frank Shamrock vs. Phil Baroni - The fight was for the vacant Strikeforce middleweight title.
- Cung Le vs. Frank Shamrock - Cung Le came into the fight undefeated. The fight was for the Strikeforce middleweight championship, with Frank Shamrock defending. Le later vacated the title and Jake Shields won it by lackluster hugfest against Jason Miller.
- Nick Diaz vs. Frank Shamrock - The fight was Nick Diaz's Strikeforce debut. Shamrock allegedly came into the bout with a rib injury sustained in training. The fight was the last fight in Shamrock's career.