[11] Santos started working in construction after graduating high school, and in his early 20s became involved in coaching with featherweight titlist Héctor Lizárraga and trainers Joe Amato and Eddie Devine.

[8] In 2022, Santos trained Dominican junior lightweight Hector Luis Garcia, who secured upset victories over Chris Colbert[12] in February and Roger Gutierrez in August.

He also guided Dominican heavy underdog Alberto Puello[13] to the WBA junior welterweight title and Carlos Adames[14] to an interim middleweight belt.

[10] Santos has worked with notable names, including Joel Casamayor, David Morrell Jr.,[15] Mario Barrios,[16][17] Rances Barthelemy, Tomoki Kameda, Livingstone Bramble, Eros Correa, and Jose Celaya.

Other boxers he was involved with include top contender Luis Nunez,[18] Cuban Olympian brothers Lenier and Dainier Pero,[19] WBA minimum world champion Erick Rosa,[20] and Amilcar Vidal.