Teenage substitute Hisai floors veteran Sitthichai with brutal uppercut at Knockout 68

Former Glory Kickboxing lightweight champion Sitthichai suffered one of the most dramatic knockouts of his career on Saturday, floored by a single uppercut from 20-year-old Taimu Hisai at Knockout 68: Knockin’ on the World in Yokohama, Japan. The finish was so violent it physically launched the 34-year-old Thai veteran into the air before he crashed to the canvas unconscious.

Hisai accepted the bout on short notice and moved up a weight class to take it — a detail that makes the result all the more striking. The teenager’s uppercut did not merely drop Sitthichai; it rendered him completely motionless on impact, leaving little doubt about the stoppage.

The loss continues a painful run for Sitthichai, widely regarded as one of the finest Muay Thai fighters and kickboxers of his generation. A former Lumpinee welterweight champion and multiple-time world title holder across striking disciplines, he had already lost four of his final five bouts in ONE Championship before departing the promotion last year, and has not recorded a victory since.

Previous recent defeats had come via body shot stoppages, but Saturday’s finish was of a different nature entirely — a clean, concussive blow to the chin that underlined how unforgiving the sport can be, even for its most decorated names.

At 34, Sitthichai now faces serious questions about the next chapter of his career, while Hisai — still only 20 and fighting above his natural weight — announced himself to the international kickboxing scene in the most emphatic way possible.