Marcus Buchecha

 ( Brazilian Practitioners Of Brazilian Jiu-jitsu ) 

In August 2020, Almeida had to withdraw from an upcoming BJJ match with Fabrício Werdum due to a knee injury that has also delayed his MMA debut for ONE FC. Almeida was scheduled to make his MMA debut against Oumar Kane at ONE Championship. Unfortunately, Almeida was removed from the card and replaced with Alain Ngalani on 13 January 2021, reportedly due to suffering an injury in training. After recovering from his injury, he was booked to make his MMA debut against Kang Ji-Won at ONE on TNT 1. Kang later withdrew from the bout for undisclosed reasons.

Almeida was scheduled to face Thomas Narmo at on September 24, 2021. Narmo later withdrew for undisclosed reasons, and was replaced by Anderson “Braddock” Silva. He won the bout in the first round via north-south choke.

Almeida faced Kang Ji Won at on December 3, 2021. He won the bout via rear-naked choke in the first round.

Almeida was scheduled to face Oumar "Reug Reug" Kane on April 22, 2022 at ONE 156. However, the week of the event, it was announced that the bout would be moved to May 20. Yet, Kane withdrew from the bout citing injury and was replaced by Hugo Cunha who in turn tested positive for COVID-19 and the bout was scrapped. Almeida was later rescheduled to face Simon Carson at ONE 158 on June 3, 2022. He won the fight by a first-round technical knockout, stopping Carson with ground and pound midway through the opening round.

Almeida faced Kirill Grishenko at ONE on Prime Video 1 on August 27, 2022. He won the bout early in the first round after submmiting Kirill with a heel hook. This win earned him the Performance of the Night award.

Almeida faced Oumar Kane on August 5, 2023, at ONE Fight Night 13. He lost the fight by unanimous decision.

A biopic entitled Buchecha: Far Beyond World Records was released in 2023.

Almeida faced Amir Aliakbari on November 9, 2024, at ONE 169. He won the fight by submission in the first round and earned a $50,000 ‘Performance of the Night’ bonus. This was the final fight of Almeida’s contract, and he became a free agent after it.

Almeida faced Kennedy Nzechukwu on December 13, 2025, at UFC on ESPN 73. Despite Nzechukwu being deducted one point due to an eye poke, the bout ended via unanimous draw.