He was a member of the gold winning Great Britain and Northern Ireland squad at the 1988 Summer Olympics in Seoul. Four years earlier, at the 1984 Summer Olympics in Los Angeles, he secured the bronze medal with his team. Kerly scored the winning goal in the bronze medal match in LA against Australia (2-1), and a hat-trick in the semi-final against the same opponent in 1988. He also participated in the 1986 World Cup in London, where England won silver.