Meet Your Professor

Rosendo Diaz

4th Degree Black Belt under Royler Gracie
30+ Years on the Mat
4° Degree Black Belt
2003 Black Belt — Royler Gracie
10+ Black Belts Promoted

Direct Gracie Lineage

Before Anyone Was Watching

Rosendo Diaz began training Brazilian Jiu-Jitsu before the first UFC aired in 1993 — before most Americans had ever heard of the art. While the rest of the martial arts world was still debating which style was superior, Rosendo was already on the mat.

This early start gave him something rare: a perspective shaped by decades of genuine evolution, not YouTube tutorials or competition trends. He learned the art when the only way to get better was to show up and be tested.

The Journey to 4th°

Pre-1993 · Early Training
On the Mat Before the UFC
Rosendo began training BJJ before the sport had a mainstream audience in North America — earning time on the mat with legends including Rickson Gracie. His foundation was built on direct transmission, not video study.
1996 · Pennsylvania
Opens The Modern Combat Academy
One of the earliest dedicated BJJ academies in the region. That same year, Rosendo began teaching defensive tactics to local and county law enforcement — where techniques had to work under real stress, against real resistance, with real consequences. It sharpened his instruction in ways competition alone never could.
2003 · Black Belt
Promoted by Royler Gracie & David Adiv
Rosendo received his black belt from Royler Gracie — 4x World Champion, 3x ADCC Champion, and head of Gracie Humaita worldwide — and David Adiv, co-founder of the RGDA association. He was also a founding member of Royler's original U.S. team. The lineage is direct, unbroken, and traceable to the first generation of Gracie Jiu-Jitsu.
2011–2023 · Team Leadership
Founds the 3rd Generation Jiu-Jitsu Team
Under his leadership, students developed over years — not weeks. Multiple students earned their black belts. Several went on to open their own academies and promote their own students, extending a genuine generational chain of knowledge.
Now · Cypress, TX & Beyond
4th Degree — Still on the Mat
Rosendo teaches at Renzo Gracie Cypress in Houston, Texas, regularly returns to Harleysville BJJ in Pennsylvania, and conducts seminars across the United States. He has never stopped teaching.

Tested for Decades

What This Means For You

Rosendo's BJJ instructionals, courses, and seminars are designed for students who want reliable, repeatable jiu-jitsu — taught with clarity, patience, and genuine respect for the learning process.

Everything presented has been tested across decades of instruction: in academies, on competition mats, and in law enforcement training rooms where the margin for error was zero. The techniques here are not trending — they are proven.

Whether you train in-person at Renzo Gracie Cypress in Houston, attend a seminar or train at the Harleysville BJJ in Pennsylvania, or work through his online BJJ instructionals on your own time — the standard is the same. Rosendo has never taught anything he hasn't pressure-tested himself.

Home Academy • Pennsylvania

Where the Lineage Lives Daily

Harleysville BJJ is more than an affiliate — it is Rosendo Diaz’s home training academy. This is where his instruction has been passed down directly, where students earned their belts under his guidance, and where his approach to jiu-jitsu continues to evolve on the mat every day.

Every instructor at the academy has trained under Rosendo — developing their skills through years of hands-on coaching, pressure-tested fundamentals, and a standard that does not change with trends.

Visit Harleysville BJJ
"He has been instrumental in shaping East Coast Brazilian Jiu-Jitsu — a pioneering figure who has never stopped teaching."