Gennady Golovkin boxes.
Gennady Golovkin . Golovkin is also said to have one of the best chins in modern boxing , having never been knocked down or knocked out in a total of 387 fights , neither as a professional nor amateur . A knockout ( abbreviated to KO or K.O. ) is a fight-ending , winning criterion in several full-contact combat sports , such as boxing , kickboxing , muay thai , mixed martial arts , karate , some forms of taekwondo and other sports involving striking . The Ring magazine Pound for Pound is the official list of the current pound for pound professional boxing rankings distributed by The Ring magazine . The Transnational Boxing Rankings Board ( TBRB ) is an all-volunteer initiative formed in October 2012 with the intention of providing professional boxing with authoritative top-ten rankings , identifying the singular world champion of every division by unbiased reasoning and common sense , and to insist on the sport 's reform .