In 1996, Marshall became coach both of Hampshire and the West Indies, although the latter's steadily declining standards during this period brought a considerable amount of criticism his way. In 1999, during the World Cup it was revealed that Marshall had colon cancer. He immediately left his coaching job to begin treatment, but this was ultimately unsuccessful. He married his long-term partner, Connie Roberta Earle, in Romsey on 25 September 1999, and returned to his home town, where he died on 4 November aged 41, weighing little more than 25 kg.