Keller Guilherme Guimarães was born in 1978 in Belo Horizonte – Brazil. He was introduced to the Martial Arts when he was just 4 years old when he started taking Judo classes for children and practicing for 7 years. During his adolescence, he simultaneously trained in Tae Kwon Do and Ninjutsu, having also practiced Muay Thai and Kung Fu for a few years.

At the end of 2000, he began his training in Brazilian Jiu-Jitsu and has been practicing since then. After 11 years of training, he successfully completed his examination and received his black belt in December 2011 by the Liga Brasileira de Jiu-Jitsu (LBJJ), a Brazilian association recognized by the IBJJF (International Brazilian Jiu-Jitsu Federation).

In July 2016, he was promoted to 1st degree black belt, also by LBJJ. He has been teaching BJJ since 2009 when he was still a brown belt. He is a member of the Equipe Leão Dourado (Golden Lion Team) in Brazil, where Grand Master Hilton Leão, a 9th degree red belt, oversees him.

Until his black belt, his instructors were Maria do Socorro Ruas (5th degree black belt) and Master José Adilson Ferreira (8th degree red and white belt). His current instructors are Fabiano Magrelo (4th degree black belt) and Grand Master Hilton Leão (9th degree red belt).

Keller is a Pharmacist and a PhD in Chemistry. He came to Kingston for the first time in 2013, when he did a year-long exchange at Queen’s University during his PhD. He and his wife moved to Kingston in September 2016. Both are researchers at Queen’s University.

In 2019, Keller was awarded the Jiu-Jitsu Builder Award for his contributions to the martial art over the years including his countless hours training and teaching the art.