UFC flyweight Allan Nascimento dies at 34 after apparent heart attack in his sleep

The death

Allan Nascimento, a Brazilian mixed martial artist who competed in the UFC flyweight division, died on Monday, 3 August 2026, at the age of 34. The UFC announced his death the same day in a statement on X, saying that Nascimento had been found unresponsive that morning after apparently suffering a heart attack during his sleep. Medical personnel dispatched to the scene were unable to revive him, and his death was confirmed at the location.

This morning, Monday 3 August, our dear flyweight fighter, Allan Nascimento, was found unresponsive after apparently suffering a heart attack during his sleep. Despite the efforts of the medical team dispatched to the scene, his death was confirmed at the location.

The organization extended condolences to his family, friends, teammates, and loved ones, describing the moment as "incredibly difficult." Nascimento, nicknamed "Puro Osso" ("Pure Bone" in Portuguese, a reference to his lean frame), was born on 11 September 1991 in São Paulo.

Career and record

Nascimento turned professional in 2011 but waited a decade before signing with the UFC, making his octagon debut in October 2021. Across his entire professional career he compiled a record of 22 wins and 7 losses from 29 bouts, with 16 of those victories coming by submission. A black belt in Brazilian jiu-jitsu, he was regarded as one of the most respected submission specialists on the UFC roster.

Inside the UFC, he fought six times, recording four wins and two losses. Between 2022 and 2025 he put together a streak of four consecutive victories. Both of his UFC defeats came by split decision. The UFC described him as "a talented competitor and a consummate professional" and noted that he was a fixture at the gates of the flyweight top 15, frequently accompanying teammates during their walkouts.

Final fight

Nascimento's last appearance in the octagon took place on 20 June 2026 at a UFC Fight Night card in Las Vegas. He faced American Mitch Raposo and lost by split decision. No one at the time imagined it would be his final professional bout. He had returned to competition roughly a year earlier after a career pause.

Tributes from Charles Oliveira

Charles Oliveira, the former UFC lightweight champion (2021–2022) and current BMF titleholder, was a close friend and teammate of Nascimento at the Chute Boxe Diego Lima gym. Oliveira posted a tribute on Instagram, saying he had lost a brother that fighting had given him.

Today I lost a brother that fighting gave me. Thank you infinitely for sharing the mats, the training sessions, and everything we lived together. I feel only gratitude for having you by my side, my brother — in training, in my corner, and in all the moments we shared.

Oliveira added that Nascimento was an extraordinary person and would be greatly missed. The two had been planning to hold a seminar together on Saturday, 8 August 2026.

Reaction

News of Nascimento's death generated an outpouring of messages from fans, fellow fighters, and members of the organization across social media. UFC Brasil issued a statement sending thoughts and deepest condolences to his family, friends, teammates, and loved ones. The sudden loss of a fighter still active and only 34 years old has left a deep void in the flyweight division and the broader MMA community.