Regian Eersel to headline The Inner Circle on April 10 against Rungrawee, Mann vs. Dzhabrailov elevated to ONE Fight Night 42 main event

ONE Championship has reshuffled its April 10 doubleheader. The vacant ONE Lightweight Kickboxing World Title fight between Regian “The Immortal” Eersel and Rungrawee “Legatron” Sitsongpeenong has moved to headline The Inner Circle. It streams live in Asia primetime from Lumpinee Stadium in Bangkok, Thailand.

Meanwhile, the welterweight MMA clash between undefeated contenders Chase “Mannimal” Mann and Dzhabir Dzhabrailov has been elevated to headline ONE Fight Night 42 on Prime Video, live in U.S. primetime.

Eersel brings a 64-5 career record and 13-1 promotional mark into the title fight. The Dutch-Surinamese fighter won both the inaugural ONE Lightweight Kickboxing and Muay Thai World Titles. That has made him one of the most decorated fighters in ONE history. He was stripped of the kickboxing belt after missing weight in April 2025 and is now hunting to reclaim it.

Standing across from him is Rungrawee, who fights out of Sitsongpeenong with a 158-48 career record and 6-2 promotional mark. The Thai striker earned his “Legatron” nickname through devastating leg kicks that have punished opponents throughout his career. He won three straight fights upon arriving in ONE before dropping two close bouts to elite competition, and comes in off a unanimous decision win over Youssef Assouik at ONE Fight Night 34 last August.

Mann vs. Dzhabrailov elevated to ONE Fight Night 42 main event

The new ONE Fight Night 42 main event is a welterweight MMA collision between two undefeated fighters with major title implications. Chase Mann arrives at 7-0 with five finishes, having made his ONE debut in January with a first-round TKO of Isi Fitikefu. The Arkansas native now gets his first U.S. primetime main event on the global stage.

Dzhabir Dzhabrailov is just 21 years old and equally unblemished at 6-0, with all six victories coming by finish. The Turkish fighter has gone 3-0 inside ONE, and has stopped all three opponents inside two minutes. His all-out attacking style leaves no room for opponents to settle.

The winner could emerge as a legitimate contender for reigning ONE Lightweight and Welterweight MMA World Champion Christian “The Warrior” Lee.