Gennadiy Gennadyevich Golovkin, often known by his nickname "GGG" or "Triple G", is a Kazakhstani professional boxer. He has held multiple middleweight world championships, and is a two-time former unified champion. He held the WBA (Super), WBC and IBF titles at varying points between 2014 and 2023, and challenged once for the undisputed super middleweight championship in 2022. He is also a two-time former IBO middleweight champion, having held the title twice between 2011 and 2023.
Sam Soliman is an Australian professional boxer, and former kickboxer and mixed martial artist. In boxing, he held the IBF middleweight title in 2014.
Sakio Bika is a Cameroonian-born Australian professional boxer. He held the WBC super-middleweight title from 2013 to 2014, and previously the IBO super-middleweight title from 2008 to 2010. In 2015 he challenged once for the unified light-heavyweight world title, and in 2007 won the third season of The Contender reality TV series.
Hassan N'Dam N'Jikam is a French Cameroonian professional boxer. He has held a middleweight world championship twice, including the WBO title in 2012 and the WBA (Regular) title in 2017, and has challenged once for a super-middleweight world title in 2019.
Daniel Geale is an Australian former professional boxer who competed from 2004 to 2016. He held the unified WBA (Super) and IBF middleweight titles between 2011 and 2013, and the IBO middleweight title from 2007 to 2009. As an amateur boxer, Geale won a welterweight gold medal at the 2002 Commonwealth Games.
Sergiy Vyacheslavovich Derevyanchenko, is a Ukrainian professional boxer who has challenged three times for world middleweight titles; the IBF title in 2018; the IBF and IBO titles in 2019; and the WBC title in 2020. As an amateur, he won the bronze medal at middleweight at the 2007 World Amateur Boxing Championships. As of February 2021, he is ranked as the world's fourth best active middleweight by the Transnational Boxing Rankings Board, eighth by BoxRec and fourth by The Ring magazine.
Daniel Jacobs is an American professional boxer. He is a two-time middleweight world champion, having held the IBF title from 2018 to 2019 and the WBA (Regular) title from 2014 to 2017. Nicknamed the "Miracle Man," Jacobs' career was almost cut short in 2011 due to osteosarcoma, a rare form of bone cancer. He went on to make a full recovery after spending 19 months out of the sport, meanwhile recovering from severe operation-induced injuries generally perceived as crippling.
Santos Saúl "Canelo" Álvarez Barragán is a Mexican professional boxer. He has won multiple world championships in four weight classes from light middleweight to light heavyweight, including unified titles in three of those weight classes and lineal titles in two. Álvarez is the first and only boxer in history to become undisputed champion at super middleweight, having held the WBA (Super), WBC and Ring magazine titles since 2020, and the IBF and WBO titles since 2021.
David Lemieux is a Canadian former professional boxer who competed from 2007 to 2022. who held the IBF middleweight title in 2015.
Gabriel Rosado is an American former professional boxer. He challenged twice for a middleweight world title in 2013. Hailing from Philadelphia, Pennsylvania, Rosado is part of the city's large Puerto Rican community. Renowned for his toughness and willingness to face elite opposition, Rosado had competed in the light middleweight, middleweight and super middleweight divisions, winning a variety of regional championships along the way.
Osumamu Adama is a Ghanaian professional boxer in the middleweight division, and the first middleweight titleholder from Ghana.
Lajuan Simon is an American professional boxer from Philadelphia, Pennsylvania that fights as a middleweight.
Gennady Golovkin vs. Kell Brook, was a professional boxing match for the unified WBC, IBF, and IBO middleweight titles. The bout was held on 10 September 2016, at the O2 Arena in London, England. The event was televised live on Sky Sports Box Office in the UK and HBO in the United States. Golovkin won the fight in round 5, after Brook's corner threw in the towel.
Darnell Lamont Boone is an American professional boxer. Despite having never challenged for a world title, Boone is notable for facing several future world champions throughout his career, from middleweight to light heavyweight. In 2004, he was the first to score a knockdown against undefeated Olympic gold medalist Andre Ward, who went on to win a unanimous decision over Boone. In 2010, Boone caused a major upset when he knocked out future world champion Adonis Stevenson, who later gained revenge by knocking out Boone in 2013. Boone also defeated Willie Monroe Jr. in 2011, who later challenged twice for a world title. Other world champions Boone has faced include Jean Pascal, Erislandy Lara, and Sergey Kovalev (twice).
Canelo Álvarez vs. Gennady Golovkin, billed as Supremacy, was a professional boxing match contested for the unified WBA (Super), WBC, IBF, IBO, Ring magazine, and lineal middleweight championship. The bout was on September 16, 2017, at T-Mobile Arena on the Las Vegas Strip. It was televised on HBO pay-per-view in the United States, on BoxNation Box Office in the United Kingdom, and on Space in Latin America.
Gennady Golovkin vs. Daniel Jacobs, billed as Middleweight Madness, was a professional boxing fight contested for the unified WBA (Super), WBC, IBF, IBO championship. The bout was on March 18, 2017 at Madison Square Garden in New York City, New York. It was televised on HBO pay-per-view in the United States, and on BoxNation in the United Kingdom.
Canelo Álvarez vs. Gennady Golovkin II billed as Final Judgment, was a professional boxing rematch between Canelo Álvarez and Gennady Golovkin which took place at T-Mobile Arena in Paradise, Nevada on September 15, 2018. Alvarez won by majority decision.
Ivan Baranchyk is a Belarusian professional boxer who held the IBF light-welterweight title from 2018 to 2019.
Kamil Szeremeta is a Polish professional boxer who held the European middleweight title from 2018 to 2019. As of June 2020, he is ranked as the world's seventh best active middleweight by The Ring and eighth by the Transnational Boxing Rankings Board.
Gennady Golovkin vs. Ryōta Murata, billed as Big Drama in Japan, was a middleweight unification professional boxing match contested between IBF and IBO champion, Gennady Golovkin and WBA (Super) champion, Ryōta Murata. The bout took place at Saitama Super Arena, Saitama, Japan on April 9, 2022.
Josue Obando
Center Stage, Charlotte, North Carolina 
Martin Fidel Rios
Gennady Golovkin 
Sam Soliman