Sean Gannon was a former UFC fighter and a Boston police officer who had a remarkable life and a tragic death. He was known for being the first man to defeat Kimbo Slice in a street fight, and for his courage and dedication as a law enforcement officer. He passed away in September 2021, but his cause of death has not been officially revealed. Here is what we know about his life, his achievements, and his demise.
A Street Fight Legend
Sean Gannon was born in Boston, Massachusetts, and grew up in a large Irish-American family. He was interested in martial arts from a young age, and trained in boxing, wrestling, and Brazilian jiu-jitsu. He also joined the Boston Police Department in 1998, and worked as a patrol officer for several years.
Gannon’s MMA career began in 2003, when he competed as an amateur for the Mass Destruction promotion. He won three fights in a row, and then turned pro in late 2003. He lost his first pro fight by submission, but bounced back with two TKO wins in 2004.
However, Gannon’s most famous fight was not in a cage or a ring, but on the streets. In 2004, he agreed to face Kimbo Slice, a notorious street fighter who had gained fame for his brutal knockouts on the internet. The fight took place in an undisclosed location, and was filmed and uploaded online. It was a bloody and brutal affair, with both men landing heavy shots and taking damage. Gannon suffered a huge hematoma on his forehead, but he managed to survive Slice’s onslaught and take him down several times. In the end, Slice could not get up from the ground, and Gannon was declared the winner by TKO.
The fight made Gannon an instant celebrity in the MMA world, and earned him a contract with the UFC. He made his UFC debut in 2005, against Brandon Lee Hinkle at UFC 55. Unfortunately, he lost the fight by TKO in the first round, and never fought for the promotion again.
A Dedicated Police Officer
Gannon’s MMA career was short-lived, but his police career was long and distinguished. He served as a patrol officer for several years, and then joined the gang unit in 2006. He was involved in many high-profile cases, such as arresting a serial rapist, busting a drug ring, and recovering stolen firearms.
Gannon was also a whistleblower who exposed corruption and misconduct within the police department. He wrote a series of articles on The Underground website, revealing how some officers abused their power, falsified reports, planted evidence, and violated civil rights. He also sued the city of Boston in 2012, claiming that he was discriminated against and placed on desk duty because of his MMA career.
Gannon alleged that he suffered from cognitive impairment and memory loss due to his fights, and that he was denied disability benefits by the city. He also claimed that he was harassed and ostracized by his fellow officers for speaking out against corruption. However, his lawsuit was dismissed by a superior court judge, who sided with the city.
Gannon continued to work as a police officer until his death in 2021. He was respected and admired by many of his colleagues and friends for his bravery and integrity.
A Mysterious Death
Gannon’s death was announced on social media by his family members and former partner on September 11, 2021. They did not reveal the cause of death or any other details about his passing. They only expressed their grief and sorrow for losing him.
“Sean ‘the cannon’ Gannon was best known as a former UFC fighter and former Boston Police Officer who gained notoriety for a street fight where he was able to defeat Kimbo Slice,” his cousin wrote on Facebook. “Less known was his brilliance – a mensa member!!; that he was like a giant loving teddy bear; one of the kindest that I know; a great father; and tenacious as hell!!”
“My heart is broken,” his former partner wrote on Twitter. “I’ve lost my best friend today.”
Many MMA fans and fighters also paid tribute to Gannon on social media, remembering him for his legendary fight with Slice and his courage as an officer.
“RIP Sean Gannon,” UFC commentator Jon Anik wrote on Twitter. “A true warrior who gave us one of the most memorable fights ever.”
“Rest In Peace Sean Gannon,” UFC Hall of Famer Bas Rutten wrote on Instagram. “You were one tough SOB who fought Kimbo Slice in one of the craziest street fights ever.”
No official statement has been released by the Boston Police Department or the UFC regarding Gannon’s death. His funeral arrangements have not been announced either.
It is unclear what caused Gannon’s death, and whether it was related to his MMA career, his police career, or something else. He was reportedly in his 40s at the time of his passing.
Sean Gannon was a unique and remarkable person who lived a life of adventure and service. He will be remembered for his achievements and his character, and he will be missed by many.
