Professional boxing knocked him out in brutal fashion. This fight made Hagler famous; he was able to lure Ray Leonard out of retirement in 1987, but lost in a highly-controversial decision. Hagler retired from boxing immediately after that fight. In the latter half of the decade young heavyweight Mike Tyson emerged as a serious contender. Nicknamed "Iron Mike", Tyson won the heavyweight unification series to become world heavyweight champion at the age of 20 and the first undisputed champion in a decade. Tyson soon became the most widely known boxer since Ali due to an aura of unrestrained ferocity, such as that
World Heavyweight Championship (Zero1) Heavyweight Championship. There have been a total of 15 recognized champions who have had a combined 22 official reigns. As of 23, 2019. World Heavyweight Championship (Zero1) The World Heavyweight Championship is a professional wrestling world heavyweight championship in the Japanese promotion Pro Wrestling Zero1. It is one of Zero1's top two singles titles, along with the NWA United National Heavyweight Championship. It was first introduced on December 15, 2007 when Zero1 ended their relationship with the AWA Superstars of Wrestling. The Superstars of Wrestling champion at the time, Masato Tanaka, was then recognized as the first Zero1 World Heavyweight