Claressa Shields

Claressa Shields stands as one of the most decorated combat sports athletes in history. A two-time Olympic gold medalist, she claimed titles at the 2012 London Olympics and the 2016 Rio Olympics, becoming the first American boxer — male or female — to win back-to-back Olympic gold medals. She went on to claim undisputed championship status across multiple professional boxing weight classes, building a legacy unmatched in women's boxing.

Her transition into MMA marked a defining crossover moment in combat sports. Shields signed with the Professional Fighters League (PFL) to pursue a new competitive chapter — one that demands proficiency in wrestling, grappling, and submission defense alongside striking. Her decision reflects a broader evolution in the sport, as elite strikers increasingly recognize that championship-level boxing credentials alone do not translate to the multi-dimensional demands of MMA competition.

Preparing for MMA competition required Shields to undertake intensive training in wrestling and Brazilian Jiu-Jitsu — areas of the game absent from her boxing background. Ground game development became a central pillar of her MMA training camps, with coaches focusing on takedown defense, positional awareness, and submission survival.

Building a Grappling Foundation

Shields worked alongside grappling coaches to develop the defensive wrestling and Guard retention skills necessary to prevent opponents from controlling her on the mat. These fundamentals — framing, hip movement, and positional recovery — form the backbone of any striker's transition into MMA, and her training underscored just how technically demanding that process is.

The Learning Curve for Elite Strikers

Her journey into grappling illustrates the steep adaptation required even of world-class athletes when entering MMA's ground-based dimensions. Building a grappling foundation at an advanced stage of an athletic career serves as a compelling case study in the physical and technical demands of modern mixed martial arts — and in the discipline required to compete at the highest level across multiple combat disciplines.