Ivanson Ranny "Johnny" Nelson is a British boxing analyst and former professional boxer who competed from 1986 to 2005. He held the World Boxing Organization (WBO) cruiserweight title from 1999 to 2006, and remains the longest reigning cruiserweight world champion of all time. Nelson defended the title against thirteen different opponents, more than any other cruiserweight in history, and holds a joint-record of most consecutive cruiserweight title defences. He also never lost the title in the ring. At regional level, he held the British cruiserweight title twice between 1989 and 1997, and the European cruiserweight title twice between 1990 and 1998.

Muamer Hukić, best known as Marco Huck, is a Bosniak, nationalized German professional boxer. He held the WBO cruiserweight title from 2009 to 2015, and is the joint-longest reigning cruiserweight world champion of all time, having made thirteen consecutive successful defenses, a division record shared with Johnny Nelson. Huck also held the IBO cruiserweight title from 2016 to 2017, the European cruiserweight title from 2008 to 2009, and has challenged once for the WBA (Regular) heavyweight title in 2012.