John Danaher

John Danaher (born 1967, Washington, D.C., United States) is a New Zealander Brazilian jiu-jitsu and Mixed Martial Arts instructor. He holds a 4th degree black belt in Brazilian jiu-jitsu under Renzo Gracie, and is an instructor at the Renzo Gracie Academy in Manhattan. Although born in the United States, Danaher grew up in New Zealand, until arriving in the United States in 1991 to study at Columbia University's philosophy PhD program. After arriving in New York, Danaher was introduced to Brazilian jiu-jitsu by a friend at the university, and began taking classes at Renzo Gracie's academy in Manhattan. He continued training at the academy and began to teach classes as well while Gracie was traveling for competition. Since receiving his black belt in the early 2000s, he has been an instructor for several notable jiu-jitsu and mixed martial arts competitors, including Chris Weidman, Georges St-Pierre, Gordon Ryan, and Garry Tonon.

John Danaher was born in Washington, D.C., United States. His father, a pilot in the New Zealand air force, acted as an attaché to the United States military during the Vietnam War. His family later returned to Whangaparaoa, a small peninsula north of Auckland, New Zealand, where Danaher spent the remainder of his childhood. He also learned kickboxing, and some karate as martial arts were becoming popular in New Zealand.

After high school, Danaher attended the University of Auckland, where he earned a Bachelor's, and later a master's degree in philosophy. In 1991, he returned to the United States to pursue a Ph.D. in epistemology at Columbia University in Manhattan. While attending the university, Danaher worked as a bouncer at various Manhattan night clubs.

While he had some striking ability from his time in New Zealand, Danaher's dedication to martial arts did not fully begin until he began training at the Renzo Gracie Academy in the early 1990s. While there, he studied under legendary jiu-jitsu practitioner Renzo Gracie, and became one of his most dedicated students, alongside Rodrigo Gracie, Matt Serra, and Ricardo Almeida. As a purple belt, he began to teach some classes at the academy while Renzo was traveling to compete in mixed martial arts competitions. Over the next several years, with many of his peers leaving to start their own academies, Danaher's responsibilities as an instructor at Renzo Gracie Academy grew, and Danaher became a full-time instructor at the school.

Being that Danaher has suffered throughout his life from severe leg and hip problems, he has never competed professionally, and as a result has devoted his time and effort to teaching. As his students have had success in competition and gained notoriety over the last several years, he has become well known as a jiu-jitsu and mixed martial arts coach, having worked closely with fighters such as Georges St-Pierre and Chris Weidman. Additionally, he coaches a group of notable jiu-jitsu competitors at Renzo Gracie Academy, often referred to as the 'Danaher Death Squad.' The group includes athletes such as Gordon Ryan, Garry Tonon, Eddie Cummings, and Nicky Ryan (Gordon's younger brother), who between them hold numerous world championships, spanning multiple organizations, including IBJJF, ADCC, Eddie Bravo Invitational, and others.

Since 2018, Danaher has been a member of Sanabul (https://sanabulsports.com/pages/team-sanabul), a premier combat sports brand, serving as a brand ambassador and consultant.

Danaher is also known for developing his own system of leg-locks and lower-body attacks. He was first introduced to the effectiveness of leg locks when Dean Lister, an American grappler who was having success in competitions utilizing leg-based attacks, came to train at Renzo Gracie Academy for two weeks in the early 2000s. With the leg lock system, Danaher was able to consolidate a large number of distinct positions and moves into a more formulaic and predictable series of procedures that could be executed by his students. Using the principles that Danaher set out in his system, his students had tremendous success utilizing leg locks in competition.

Danaher is credited with helping to alter the jiu-jitsu community's opinion of leg locks, as many saw them as a non-technical and ineffective method of attack before Danaher's students demonstrated their usefulness in competition. Danaher has since developed systems for various types of arm attacks, as well as back and strangle-based attacks.

Having been born with deformed patellas, Danaher was prone to knee injuries throughout his early years. In the 1980s, Danaher suffered a severe knee injury to his left leg while playing rugby, which required surgery. The result of multiple surgeries on his left knee was artificially shortened and deformed ligaments, which drastically inhibited Danaher's ability to properly extend and retract his knee. Over the years, this imbalance proceeded to cause other problems for Danaher. Namely, an unbalanced gait caused Danaher's left hip to be subjected to undue force and strain, leading to severe osteoarthritis. The damaged hip ultimately required a replacement, which Danaher underwent in 2015.

In 2017, Danaher appeared in four episodes of the Showtime series Billions, in which he portrays the jiu-jitsu instructor of U.S. Attorney Chuck Rhoades (Paul Giamatti). In 2012, he appeared as himself on the Spike TV series MMA Uncensored Live episode “King Mo Reigns”.

In 2015, Danaher co-starred in the documentary "Jiu Jitsu vs the World" alongside renowned Brazilian jiu-jitsu practitioners Eddie Bravo, Renzo Gracie, and Roberto Abreu, among others.