Coaches & Lineage
When you train at Sitjaroonsak, you step into a family-run Muay Thai gym with a real fight history: Kru Charoon, Anna ‘Supergirl’ Jaroonsak, Nat ‘Wondergirl’ Jaroonsak, Ratanachai Sor Vorapin, Kru Preecha, and the coaches who keep that teaching alive in Bang Wa.
Bang Wa
Original Bangkok home
ONE
Anna and Nat Jaroonsak
WBO
Ratanachai Sor Vorapin
Jaroonsak Family
The story begins in a small Bangkok gym in Bang Wa: a father-coach from the Sor Vorapin line, two daughters raised through daily training, and a coaching method that later reached ONE Championship.
Jaroonsak family founder
The family teacher behind Anna and Nat Jaroonsak. Siam Fight Mag documents him as the owner of Jaroonsak Muay Thai Gym, a former Sor Vorapin representative, and the father-coach who built the sisters from home training.
Siam Fight MagONE Championship striker
Raised in the Jaroonsak system and known internationally for her knee attacks. ONE lists her team as Jaroonsak Muaythai, while Siam Fight Mag traces her early training back to her father and the family gym.
ONE athlete profileMuay Thai and MMA athlete
The older Jaroonsak sister, also raised in Bangkok through the family Muay Thai household. ONE lists her as Jaroonsak Muaythai / Southside MMA and notes her national titles before joining ONE Championship.
ONE athlete profileTechnical Coaches
Former WBO Bantamweight Champion
Boxing and Muay Thai technical direction
Ratanachai brings championship boxing mechanics into the Sitjaroonsak syllabus: balance, stance discipline, counter timing, and hand positioning built for real pressure.
Fairtex Pattaya pedigree
Muay Thai technical coach
Kru Preecha adds an experienced trainer's eye: correction-heavy pad work, clean basics, distance control, and the practical rhythm of old-school Thai instruction.
The reference point is the Jaroonsak approach: simple, repeatable, correction-led training adapted to the student's body, timing, and level.
Ratanachai's boxing background sharpens the hands, feet, guard, and counter structure inside a Muay Thai rhythm.
Kru Preecha's value is in the details: distance, balance, rhythm, and the small adjustments that change how a technique lands.
Independent References
These outside profiles and articles are useful if you want to understand the people behind the gym before you visit: the Jaroonsak family, Anna and Nat in ONE Championship, Ratanachai's boxing career, and Kru Preecha's Fairtex background.
Siam Fight Mag
Documents Bang Wa, Kru Charoon, the Sor Vorapin connection, and the rise of Anna and Nat.
Siam Fight Mag
Adds biographical detail on Anna, Nat, and the family training history.
ONE Championship
Official ONE profile for Anna, including her team and fight history.
ONE Championship
Official ONE profile for Nat, including her team and fight history.
Wikipedia
A public overview of Ratanachai's boxing career, record, and WBO title history.
Siam Fight Mag
Fairtex Pattaya report naming Preecha among recognized trainers.
