Nicholas de Barcellos Meregali was born on 27 May 1994, in Santo Antônio in the Brazilian state of Rio Grande do Sul.

[8] During his first year as black belt Meregali won the 2017 World Jiu-Jitsu Championship by beating division favourite Leandro Lo, one of the greatest BJJ competitors of all time, 2–0 in the final.

[9] The next year, Meregali won gold medal in the Super Heavyweight division of the Brazilian National Jiu-Jitsu Championship, submitting his opponent from the back in the final.

After showing his middle finger to a spectator who was heckling him, Meregali was disqualified from the 2021 World Championship halfway through the ultra-heavyweight semi-final match,[10] before the disqualification, he was considered to be on track to win both gold at his weight division and in Absolute.

[13] Meregali has been described as having a "complete game," and he is known for his outstanding guard, especially his innovative use of the De La Riva position, and chokes from the back.

[14][1] Meregali transitioned to no gi competition in 2022, making his debut against Arnaldo Maidana at Who's Number One and winning by armbar.

[15] In preparation for his first attempt at the ADCC world championships,[16] Meregali started training No-Gi at the New Wave Jiu Jitsu academy in Austin, Texas, under head coach John Danaher.

[24] Meregali was scheduled to compete against Roberto "Cyborg" Abreu at UFC Fight Pass Invitational 4 on June 29, 2023.