UFC fighter Allan Nascimento has died at the age of 34 after suffering an 'apparent heart attack' in his sleep.

It comes just six weeks after the Brazilian's last fight in Las Vegas on June 20. He suffered a split decision loss to Mitch Raposo at UFC Vegas 119.

A UFC statement read: 'This morning, Monday, August 3rd, our beloved flyweight fighter, Allan Nascimento, was found unresponsive after suffering an apparent heart attack in his sleep.

'Despite the efforts of the responding medical team, he was pronounced deceased at the scene.

'Our thoughts and deepest condolences are with Allan's family, friends, teammates, and loved ones during this incredibly difficult time.'

The UFC's statement was accompanied by a single black-and-white photo of him smiling, while holding up his fist in a UFC boxing glove.

Born in Sao Paulo, Nascimento built an impressive reputation by winning 17 of his first 22 fights. 

A flyweight, the 'Puro Osso' - a Portuguese idiom meaning 'skin and bones' - competed in multiple promotions during his career, including RIZIN, Legacy FC and Dana White's Contender Series.

Nascimento then joined the UFC in 2021 and won four of his six fights. He finished his career with a 22-7 professional record.

He managed to secure the Performance of the Night bonuses for impressing fans in submission victories over Carlos Hernandez and Cody Durden. 

Former UFC lightweight champion Charles Oliveira, who trained with Nascimento in Sao Paulo, posted an emotional tribute on social media. 

He wrote in Portuguese: 'Today I lost a brother that the fight game gave me. Thank you for always being by my side, for sharing the mats and the corner.

'I have nothing but gratitude for having you with me - in training, in the corner, and just hanging out. I love you, man; you're a legend. My brother, I can’t even believe it; you will be deeply missed.'