UFC 23 was the second UFC event to take place in Tokyo, Japan, where the newly formed PRIDE Fighting Championships were enjoying massive success. UFC 23 was headlined by a Heavyweight Championship Title bout between Kevin Randleman and Pete Williams, held to determine the champion after Bas Rutten's retirement. Bas Rutten announced on UFC 23 that he dropped his heavyweight championship title so he could drop down to middleweight to bring Frank Shamrock out of retirement to fight for the middleweight championship.