Marcos "Ratinho" Santana was born on August 15, 1986, in São Gonçalo, Rio de Janeiro, Brazil. Before finding his calling on the mats, he spent his formative years as a five-a-side goalkeeper — a position demanding sharp reflexes and spatial awareness, qualities that would translate directly into his future as a grappler.
It was his elder brother Paulo César who first opened the door to jiu-jitsu, drawing Marcos into the sport in 1999. The timing carried real weight. Rio de Janeiro was then gripped by the notorious "Pitboy" era, a period in which BJJ had developed a deeply troubled public image due to groups of aggressive young men who used the martial art to instigate street violence across the city. The sport's reputation was toxic enough that the brothers' parents strictly forbade them from training, forcing Marcos and Paulo to practice in secret.
Their earliest sessions were entirely informal — Paulo had begun drilling positions with college classmates without qualified supervision, and Ratinho gradually joined the group, learning through repetition and peer-based practice. Unconventional as it was, this period forged a raw competitive instinct and a deep love for the art that would define his path forward.
Between 2000 and 2001, Marcos spent just over a year in João Pessoa, in the northeastern state of Paraíba, where he received formal instruction for the first time. His coach there was Eduardo Machado of the Carlson Gracie/Mario Sukata Academy, under whom Ratinho earned his blue belt — the milestone that marked the beginning of his structured jiu-jitsu development.