Gennady Golovkin boxes.
Gennady Golovkin . Golovkin won his first major world championship , the WBA interim middleweight title , by defeating Milton Núñez in 2010 . Milton Núñez ( born September 25 , 1987 ) is a Colombian middleweight boxer . Nunez 's biggest fight was against Gennady Golovkin for the interim WBA middleweight title .