I had a UFC clip of his open in another tab when my husband told me he'd died. 34. In his sleep. Heart attack. I don't even follow this sport closely but that stopped me cold.
Their story
Allan Alves do Nascimento, known throughout mixed martial arts as "Puro Osso", was a Brazilian flyweight who fought for the Ultimate Fighting Championship from 2021 until his sudden death in August 2026 at the age of 34. A lifelong son of São Paulo and a proud product of the Chute…
Allan Alves do Nascimento, known throughout mixed martial arts as "Puro Osso", was a Brazilian flyweight who fought for the Ultimate Fighting Championship from 2021 until his sudden death in August 2026 at the age of 34. A lifelong son of São Paulo and a proud product of the Chute Boxe Diego Lima academy, he built a 22 and 7 professional record over fifteen years, won regional titles in Brazil, fought in the United States and Japan, and earned two UFC Performance of the Night bonuses.
Nascimento was born in São Paulo on 11 September 1991 and was raised there. He began training Muay Thai at 15 after a schoolmate suggested it, and Diego Lima became his coach from that first year. He later said that he was so thin when he joined the academy that teammates immediately called him "Puro Osso", which means "just bones" in Portuguese. The nickname stayed with him for the rest of his career. His family was not keen on fighting at first, and he competed as an amateur without telling them. Before his professional debut he had a frank conversation with his parents about the life he wanted, and they came to support him.
He made his professional debut in 2011, winning by triangle choke at Thai Fight 3 in São Paulo, and quickly established himself as a submission specialist. In 2012 he won the Predador FC bantamweight championship and also travelled to Houston to win at Legacy FC. In 2013 he fought for the Legacy FC flyweight title in Dallas, losing a decision to Will Campuzano. In October 2016 he won the vacant Gold Fight flyweight championship over five rounds, and two months later he fought in Japan at the Rizin World Grand Prix, losing a split decision to Yuki Motoya in Saitama. Fifteen of his 22 professional wins came by submission.
In August 2018 Nascimento was invited to Dana White's Contender Series Brazil, where he lost a split decision to Raulian Paiva in a fight he described as a battle. The years that followed were hard. Four scheduled fights fell through, including one card in Miami that was cancelled on fight day after he had weighed in, and he needed surgery for injuries. In 2021 a fight in Ecuador was cancelled 20 days out. He said later that he had to rethink his career choice and that he kept going on faith. In July 2021 he accepted a fight at Punho de Aço 6 on one week's notice, submitted Elivaldo Lima Martins in the first round, and received his UFC offer two days later.
He made his UFC debut at UFC 267 in Abu Dhabi on 30 October 2021, losing a split decision to the unbeaten Tagir Ulanbekov. In May 2022 he won his first UFC fight with a unanimous decision over Jake Hadley in Las Vegas, and in January 2023 he submitted Carlos Hernandez with a rear-naked choke in the first round, earning his first Performance of the Night bonus. Injuries and illness then cost him several bookings, but he returned in May 2025 with a unanimous decision win over Jafel Filho and followed it in November 2025 with an anaconda choke submission of Cody Durden, his fourth straight win and second Performance of the Night award. His final fight was on 20 June 2026 in Las Vegas, when he lost a close split decision to Mitch Raposo. His UFC record stood at four wins and two losses.
Inside Chute Boxe, Nascimento was known as a training partner and cornerman for former UFC lightweight champion Charles Oliveira, and as a coach and motivator for younger students. He trained jiu-jitsu at the B9 academy in São Paulo under Marco "Barbosinha" Barbosa and held a black belt in Muay Thai. He lived in São Paulo all his life, most recently in the Morumbi district, and he left a wife and two children.
On the morning of Monday 3 August 2026, Nascimento was found unresponsive at his home after an apparent heart attack in his sleep. Despite the efforts of the responding medical team, he was pronounced dead at the scene. The UFC announced his death the same day, calling him "our beloved fighter and exemplary flyweight". He was buried on 5 August 2026 at Cemitério Congonhas in São Paulo after a wake attended by more than 200 people. Teammates carried his casket, mourners formed a guard of honour and applauded, and white and blue balloons were released. Charles Oliveira promised that his legacy would never be forgotten, Chute Boxe called him "a warrior, friend, dedicated competitor and extraordinary human being", and UFC president Dana White called his death "one of those freak, tragedy things that happened to a young guy that it shouldn't happen to." He is remembered as a durable, exciting fighter who waited years for his chance and made the most of it.
Biography adapted from UFC statement (3 Aug 2026); ESPN; The Guardian; Al Jazeera; BBC Sport; Sky News; The Independent; Sherdog (12 Questions, Oct 2021; funeral report, Aug 2026); ge.globo; CNN Brasil; Band; Cageside Press. Wikipedia ↗
In their own words
“When I joined my academy, I was extremely thin. I weighed nothing. As soon as people saw me, they called me "Puro Osso." The nickname stuck.”
Explaining his nickname to Sherdog, October 2021
“Thankfully, I kept my faith, and today, I'm under contract with the UFC.”
On years of cancelled fights before his UFC signing, Sherdog, October 2021
“Russians may be cold, but Brazilians never back down.”
Before his UFC debut against Tagir Ulanbekov, Sherdog, October 2021
“Everyone who knows me knows that my name always goes along with Chute Boxe.”
On his team, Sherdog, October 2021
“The Chute Boxe spirit is what I'll bring into the Octagon. It's a different attitude.”
On his fight preparation, Sherdog, October 2021
“Obrigado @UFCBrasil por toda torcida e energia sempre, lá em cima é por vocês, representamos uma nação forte guerreira e apaixonada por esse esporte ! Cada vitória é por vocês”
Thanking Brazilian fans on X after beating Cody Durden, 2 November 2025
“Allanzito, you were always an example of commitment, discipline and character to our team. Be sure your legacy will never be forgotten.”
Charles Oliveira, after Nascimento's funeral, August 2026

same, saw it trending and thought it had to be a mistake