John Coker boxed for Sierra Leone at the 1968 Olympics, carrying his nation’s flag at the Opening Ceremony. He grew up in Ireland, attending St. Peter’s College, York, then Trinity College, Dublin, before going to St. Catherines, Oxford. He began playing rugby as a wing three-quarter for Dublin University FC First XV for four years, and took up boxing at the Dublin University Boxing Club. At Oxford Coker was a double boxing and rugby Blue, and was the first indigenous African to win a rugby Blue. In 1963 Coker won the Leinster heavyweight title, and in 1964 won an All-Ireland bronze medal as a junior. He moved up to senior in 1965, winning heavyweight bronze.