Allan 'Puro Osso' dies at 34, victim of a possible heart attack.

Pure Bone at a UFC event. Photo: Reproduction/Facebook/UFC

PUBLICITY:

Brazilian fighter Allan Nascimento, better known as 'Puro Osso', died this Monday (3), at the age of 34, in São Paulo. The fighter, representing the Chute Boxe – Diego Lima team, had last fought at UFC Vegas 119 , held on June 20. He was found dead with signs of cardiac arrest.

The news was confirmed through a post on the official UFC social media channels in Brazil.

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"On the morning of Monday, August 3rd, our beloved flyweight fighter, Allan Nascimento, was found unresponsive after suffering an apparent heart attack while sleeping. Despite the efforts of the medical team that provided care, death was declared at the scene," the organization wrote.

Allan Puro-Osso was a UFC veteran.

Allan "Puro Osso" celebrating his victory at UFC Vegas 110. Photo: Reproduction/Instagram/UFC

PUBLICITY:

Training partner of names like Charles do Bronx at the Chute Boxe-Diego Lima gym, Allan Puro Osso competed in six fights over five years as an athlete in the world's largest MMA event, with four wins and two losses. In addition, he also had eight fights canceled, which made it difficult for him to have a longer run in the company.

His last fight was on June 20th of this year, when he was defeated by Mitch Raposo by split decision on the preliminary card of UFC Vegas 119. In total, he built a record of 22 wins and seven losses.

Allan "Pure Bone" was one of Charles "Do Bronx" Oliveira's closest friends at Chute-Boxe.

Allan "Puro Osso" was one of the great friends and partners of champion Charles "Do Bronx" . At UFC Rio, held in October 2025, as soon as he submitted Mateusz Gamrot in the main event, Charles went to the stands and hugged his "brother" Puro Osso (see video below).

On his social media, Charles do Bronx made a point of paying tribute to his friend.

"Today I lost a brother that fighting gave me. Thank you for always being there, for sharing the mat, the corner, for the words. I only have gratitude for having you by my side, brother. In training, in the corner, in the banter. I love you, kid. You were awesome," wrote Charles do Bronx on Instagram.

Charles do Bronx pays tribute to Allan Puro Osso . Photo: Reproduction / Instagram.

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