Martin began playing wheelchair sport during rehabilitation, and soon excelled at table tennis, defeating the New South Wales champion. At the 1964 Tokyo Paralympics, he won a silver medal in the Men's St. Nicholas Round Team open event. He participated in the 1966 Commonwealth Paraplegic Games in Kingston, Jamaica, where he won three gold, four silver and two bronze medals. At the 1968 Tel Aviv Paralympics, he participated in athletics, table tennis, wheelchair basketball and wheelchair fencing, winning two silver medals in the Men's Slalom B and Men's 4x40 m Relay open events. He won several medals at the 1970 Commonwealth Paraplegic Games in Edinburgh, and equalled the world record in the 100 m at the 1970 Australian National Championships in Melbourne, the qualifying event for the Edinburgh games. At the 1972 Heidelberg Paralympics, he severely cut his hand during a wheelchair basketball game, which virtually ended his campaign; apart from wheelchair basketball, he participated in athletics events at the games, but did not win any medals. He won three gold and two silver medals in the 1974 Commonwealth Paraplegic Games in Dunedin. He went to each Stoke Mandeville Games from 1974 to 1981 and won gold medals in the pentathlon in 1974 and 1975. In 1975, he won five gold and three silver medals at the first FESPIC Games in Japan. That year, he was the first person in a wheelchair to compete in Sydney's City2Surf race; the organisers did not allow him to participate in the previous two events because they did not think he could complete the course.