These waters are dangerous. Diogo Reis, aka ‘Baby Shark’, cruised through the no-gi featherweight bracket at the Rio Spring International Open, a CBJJ tournament held in Rio de Janeiro on Friday, October 16. Three matches, three submission wins, and a gold medal.
The leader of Ágora Jiu-Jitsu put his game on display and showed, as always, a uniquely deep technical arsenal. His opponents found no openings, and ‘Baby Shark’ left the mat without a scare. Zero danger and one more title for the collection.
SHARK ON THE RISE: TWO-TIME ADCC CHAMPION DIOGO REIS ADDS ANOTHER GOLD TO THE COLLECTION
Developed in Manaus, Diogo Reis has established himself as one of the most dangerous lighter-weight names in world grappling. At ADCC, the biggest submission tournament on the planet, he won the under-66kg title in 2022. Two years later, he did it again, beating Diego ‘Pato’ in the final.
The back-to-back titles made ‘Baby Shark’ the first to win two straight editions of the division since Rubens ‘Cobrinha’ Charles. In December 2025, Diogo also captured the ONE FC flyweight submission grappling belt in Thailand, beating Japan’s Daiki Yonekura by unanimous decision.
The nickname started as a joke about the athlete’s size and took off with the children’s song that went viral around the world. The shark hat became his trademark on the podium, and Rio was no different.
KING OF ONE: THE MANAUS NATIVE WAS NAMED THE PROMOTION’S BEST GRAPPLER OF 2025
The ONE FC belt capped a flawless season. Before facing Daiki Yonekura, Diogo Reis had already beaten Japan’s Shoya Ishiguro in his debut for the Asian promotion. In the title fight, for a belt left vacant since Mikey Musumeci’s departure, the Brazilian passed the guard with a knee cut, applied pressure from side control and even locked in an arm triangle before sealing the unanimous decision. It was confirmation that the two-time ADCC champion is in one of the best stretches of his career.
The run earned him recognition. In January 2026, ONE FC named Diogo Reis its best submission grappling athlete of the 2025 season. The award put ‘Baby Shark’ at the top of a promotion that has become one of the main showcases for professional grappling and that once had Mikey Musumeci as the holder of that same belt.
With the ONE title and two ADCC golds on his résumé, the athlete keeps splitting his schedule between professional events and IBJJF tournaments. His run at Rio Spring shows that, even at his peak, Diogo still makes time for smaller events and takes on whoever is in front of him.
This article was originally published in Portuguese: read the original version.
