Gutierrez mere mbido ya na Mexico na Eprel 30, 1989, mgbe ọ dị afọ iri na anọ. Ọ bụ nwanne nna ya Rey Misterio Sr. zụrụ ya ma lụọ ọgụ na mbido na Mexico ebe ọ mụtara Lucha Libre elu elu na-efe efe nke abụrụla akara ya. O nwere aha mgbanaka dịka "La Lagartija Verde (The Green Lizard) " na "Colibrí (Humming bird) " tupu nwanne nna ya nyere ya aha Rey Misterio Jr. Na 1991, Mysterio nwetara "Most Improved Wrestler" na Mexico ka ọ na-alụ ọgụ dị ka Colibrí. Ajụjụ: Afọ ole ka Rey Misterio Jr. dị mgbe o mere mbido ịgba mgba Lucha Libre ya?
Ọ dị afọ iri na anọ mgbe ahụ.