In 1995, Marcello traveled to the United States to deepen his training under Rickson Gracie, spending three years dedicated to refining his understanding of leverage, control, and submission finishing — core principles that would define his game. Returning to Brazil in 1998, he transitioned into Vale Tudo competition, testing his grappling skills in a full-contact fighting context. It was Royler Gracie who ultimately awarded Marcello his black belt, cementing a lineage tracing directly through one of BJJ's most influential family branches. The enduring relationships Marcello maintained with both Rickson and Royler across multiple phases of his development reflect the depth of trust and mutual respect at the heart of his BJJ journey.