According to his own account, Onofre often competed and won in local athletic races in his hometown of Dagupan barefooted prior to entering high school.

[2] Onofre initially competed in men's high jump in regional private school meets and was scouted by coaches of the Philippine athletics team becoming a candidate for the 1958 Asian Games in Tokyo.

He shifted to 100 and 200-meter runs since he felt inadequate in high jump and he eventually secured a berth in the men's 4x100-meter relay squad with Remegio Vista, Isaac Gomez and Claro Pellosis; all gold medalists in the 1958 Games.

Onofre along with Vista, William Mordeno, Arnulfo Valles took part in the 4x100-meter relay at the 1966 Asian Games in Bangkok where they settled for bronze.

He also has a granddaughter; Zion Corales Nelson who became an athlete like himself, who won a silver in the women's 4x100 meter relay in the 2019 Southeast Asian Games.