The Mexican, who went from minimumweight up to super-fly, suffered the devastating injury in a sixth round knockout defeat to David Cuellar Contreras in October 2021.
He was swiftly rushed to hospital, but now it has been confirmed by WBC president Mauricio Sulaiman that Fuentes passed away on Thursday morning.
Sulaiman posted the news social media, saying: “Thank God, Moises Fuentes is already resting in peace. A warrior who fought to the last breath.
“Our condolences to his family and friends and our appreciation to his wife for her dedication and dedication with indescribable love during this difficult year of suffering.
“May he rest in peace.”
Fellow Mexican boxer Sulem Urbina also paid tribute to Fuentes, saying: “Moises Fuentes last fought Oct 2021 was knocked out. Since then had surgery and battled a whole year to try and stay here for his family.
“Today he says goodbye. Today I ask the boxing world not to forget him. Today ask to respect boxers and pray every time one steps in the ring.
“It was a pleasure to coincide with you in this life friend. Rest in peace Moises Fuentes.”
While a fan added: “Damn. Horrible news regarding the passing of Moises Fuentes. He shared the ring with the very best from 105 to 115. Rest in peace, Champ.”
And another said: “Ahh man 😢 Rest in peace to Moises Fuentes!”
Fuentes won 25 of his 34 professional bouts, with 14 victories coming by way of knockout.
In 2011, he became WBO minimumweight world champion by winning a split decision against Raul Garcia in Guadalajara.
He then attempted to become a two-weight world champion in 2013, fighting Donnie Nietes for the light-flyweight title in the Philippines.
And while he produced an impressive display, it ended in a split decision draw.
He stepped away from boxing in 2018 after two knockout defeats in a row – including a first round KO loss to WBC flyweight champion Daigo Higa.
But Fuentes then returned in 2021 after more than three years out of the ring, only to lose to Cuellar and suffer the heartbreaking brain clot in the process.