There are certain dates that carry weight beyond their position on the calendar, and Saturday, February 14, promises to be one of them for someone.
Inside Lumpinee Stadium in Bangkok, Shadow Singha Mawynn and Nico Carrillo will settle the question of who wears interim gold at featherweight while Tawanchai PK Saenchai nurses a leg injury on the sidelines.
It is the second title showdown added to ONE Fight Night 40, and it represents the kind of opportunity that can define careers — the chance to leave that historic arena with championship gold secured around one’s waist, even if temporarily.
Carrillo’s journey through ONE Championship reads like a masterclass in controlled destruction. The twenty-seven-year-old from Glasgow announced himself with authority in April 2023, dismantling Furkan Karabag via third-round TKO in his promotional debut at featherweight.
Then came the decision that separates the confident from the foolhardy — dropping down a weight class to face the beloved Muangthai PK Saenchai, whom he stopped in the second round to earn his six-figure contract.
The Scottish slugger proceeded to knock out former longtime ONE bantamweight Muay Thai world champion Nong-O Hama and former title challenger Saemapetch Fairtex, each victory another statement that he had arrived and intended to stay. The interim gold seemed inevitable until January 2025, when the 6-foot-4 skyscraper Nabil Anane handed him his first promotional defeat at ONE 170.
That loss prompted the kind of honest self-assessment that separates journeymen from champions. Carrillo returned to featherweight, where his body didn’t scream in protest at making weight, where he felt healthiest and strongest.
The decision proved inspired — he knocked out seven-time Muay Thai and kickboxing world champion Sitthichai Sitsongpeenong in April 2025, then stopped American standout Luke Lessei seven months later.
Now riding a two-fight knockout streak at his proper weight, Carrillo seeks the gold that has so far eluded him. His resume at featherweight remains unblemished, and at ONE Fight Night 40, he’ll attempt to add interim championship status to that immaculate record.
Standing across from him will be Shadow, a twenty-five-year-old Bangkok resident who entered ONE Championship carrying the Rajadamnern Stadium Muay Thai championship and promptly stumbled in his February 2024 debut. What followed was the kind of response that reveals character — five consecutive victories over increasingly dangerous opposition.
Shadow demolished former ONE world title challenger Jimmy Vienot, recent contract winner Mohammad Siasarani, and even Sitthichai — the same legend Carrillo would later knock out, creating a peculiar thread of connection between these two knockout artists.
After stopping Hassan Vahdanirad at ONE Friday Fights 100 in March 2025, Shadow earned his own six-figure contract and global roster spot.
His first appearance as a contracted fighter against Mohamed Younes Rabah ended prematurely in a no contest due to an accidental eye poke in July 2025, but the Thai responded with the kind of finish that makes highlight reels immortal. He landed a spinning backfist that separated WBC Muay Thai world champion Bampara Kouyate from consciousness two months later.
Both men represent the finest contenders in ONE Championship’s featherweight Muay Thai division, each carrying knockout power that has left opponents unconscious and fans breathless.
The mathematics are simple — winner claims interim gold and secures a future unification bout with Tawanchai once the champion’s leg heals. The execution will be anything but.
Carrillo brings the urgency of a man who’s tasted defeat and found the experience sufficiently unpleasant that he’s determined never to sample it again.
Shadow carries the confidence of a fighter who’s overcome early stumbles to establish himself as one of the most dangerous strikers in the weight class. On Saturday the 14th in Bangkok, with the world watching, one of them will leave Lumpinee Stadium with gold around his waist and the other will be left to recalculate his path to championship glory.
