"By my rough calculation, I have spent at least 2,400 hours on the mats (if not more). It has been a long journey with many ups and downs (and injuries), but I would not change any of it," wrote Sityodtong on his Instagram post marking the event.

"I have been submitted more times than I can remember. I have gone home discouraged more times than I care to admit. I have wanted to give up more times than I can count. For sure, I am not the most talented jiu-jitsu student, but my love for the gentle art is unbreakable. "

ONE's leader has been a lifelong martial artist. The latest promotion marks a significant moment in his own athletic career. The entrepreneur has fully embraced the grappling arts to go along with his striking background.

And the belt presentation was special as well.

Former ONE Strawweight World Champion Alex "Little Rock" Silva wrapped the coveted belt around his waist. The Evolve MMA representative is a World Champion Brazilian Jiu-Jitsu artist and has helped train ONE's CEO and Chairman along his own journey.

When thanking his list of trainers and training partners, Sityodtong wrote, "Each of you gave me a piece of your game and generously shared your love of the gentle art with me. You beat me up and made me suffer, but I am eternally grateful for all of the lessons on and off the mats."

The hard work is not over. ONE's charismatic leader will continue his training and perhaps one-day exchange brown for black.