Justin Flores

Justin Flores built one of the most consequential coaching records in modern combat sports, serving as the personal coach of Ronda Rousey through six successful UFC bantamweight title defenses. His work with Rousey centered on translating classical judo technique into the MMA context — throws such as O-Goshi and Harai Goshi, paired with the armlock Juji-gatame, formed the core of her fight-ending arsenal. The results carried lasting historical weight: Rousey's championship run reshaped how the sport understood women's combat athleticism, and Flores was central to the technical architecture behind it.

Following his years with Rousey, Flores expanded into national team leadership, serving as USA Judo's team coach for the Tokyo 2020 Olympics. The appointment marked a deliberate transition — from the one-on-one intensity of MMA coaching to the broader logistical and technical demands of guiding a national delegation at the Games' highest level. He also serves as a USA Judo Olympic instructor, a role that places him at the intersection of competitive judo development and elite combat sports preparation.

Framing the Comparison

On the JudoPod podcast in September 2026, Flores offered an extended public comparison between Ronda Rousey and Kayla Harrison — who held the UFC bantamweight championship as of that date — framing the two athletes as representatives of fundamentally different eras and philosophies in women's MMA.

Harrison: The Complete-Athlete Blueprint

Flores rooted his characterization of Harrison in structure and method. He described her approach as scripted and chess-like — built around double-leg takedowns, the jab, and ground-and-pound, with a clear emphasis on foundational MMA strategy over flash. In his view, Harrison embodies the complete-athlete blueprint: a calculated, control-oriented system that prioritizes consistency and minimizes exposure.

Rousey: Explosive Sequences and Revolutionary Impact

Rousey, by contrast, operated in an entirely different register — one defined by explosive, ultra-fast sequences that left observers struggling to process what had occurred. "Ronda could go out there and make like the seven second exchange happen that was like, how the heck did that happen," Flores said, elaborating on her broader significance: "That's where Ronda was like, you know, revolutionary in her, you know, combat style, where, you know, a lot of people had never seen anything that resembled what Ronda did, even to this day [as of September 2026]."

Despite their shared judo foundation — both athletes incorporate O-Goshi, Harai Goshi, and Juji-gatame within their MMA approaches — Flores noted that Rousey and Harrison are rarely discussed in the same breath, which he called "too bad." The contrast, in his framing, reflects genuine philosophical divergence: Rousey as a phenomenon whose power derived from surprise value and explosive clinch-based dominance; Harrison as a methodical architect whose strength lies in control and process.

The Physical Reality

Few coaches in any grappling discipline have continued to teach and compete under the physical constraints that Flores carries. By his own account — shared on the BJJ Fanatics Podcast in October 2025 — he has undergone approximately 18 knee surgeries, including six ACL reconstructions. He lacks functional ACLs and PCLs, lives with severe arthritis, and retains minimal cartilage in his right knee. A substantial bone growth that developed over roughly the decade between 2015 and 2025 further restricted knee mobility until it was surgically removed around 2023. He also reports three herniated discs in his neck, a condition that limits head movement and can produce numbness and stinging sensations down the arms.

A Restructured Technical Framework

Rather than stepping away from the mat, Flores has rebuilt his technical approach around these realities. He avoids the head-to-head pressure and force-on-force driving that characterizes wrestling-heavy grappling — methods that place unacceptable loads on his cervical spine and compromised knees. In their place, he favors efficient, opportunistic takedowns: entries timed to opponents' overconfidence rather than powered through physical dominance. One notable adaptation involves entering to the legs by passing an elbow to a leg rather than driving through the opponent's body, a modification that meaningfully reduces loading on the neck.

The practical relevance of this injury-adapted methodology extends well beyond his own circumstances. For grapplers managing long-term physical limitations — particularly in no-gi and submission grappling contexts where explosive, impact-heavy wrestling entries are common — Flores's framework offers a studied alternative grounded in timing, leverage, and energy efficiency. He continues to teach and demonstrate technique, remaining competitive despite chronic pain, and cites the responsibility of being a father of two as part of what keeps him engaged and present on the mat.

In November 2024, Flores announced that he was considering launching a hybrid no-gi judo tournament under the name the JFLO Invitational. The concept positions itself at the intersection of traditional judo competition structure and the no-gi rulesets that have become increasingly central to the submission grappling and BJJ competition landscape.

The proposal reflects a broader interest in expanding judo's competitive footprint into formats that do not require a formal judo background to enter — an approach designed to draw competitors from BJJ, wrestling, and submission grappling communities who engage with judo technique but compete outside the gi-based traditional circuit. No confirmed details regarding format, weight classes, or a launch timeline had been publicly established as of the announcement.