In the
1984 State of Origin series Jack made his New South Wales début and played in all three games of that year's series. He was thereafter the Blues' first choice fullback for the next six years, aside from the 1987 fourth game exhibition match in Los Angeles when he made himself unavailable, and game I of 1988 when
Cronulla's
Jonathon Docking was preferred. Jack made 17 appearances for
New South Wales in
State of Origin series between 1984 and 1989. In 1984, he also made his international début in the three match
Ashes series against Great Britain. He played twenty successive Tests (nine versus Britain, seven against
New Zealand and two each against France and Papua New Guinea) as well as the 1988
World Cup Final against New Zealand and the Bicentenary International against a Rest of the World team. On the
1986 Kangaroo tour, Jack played in all six Tests and seven minor Tour matches. He became the first Australian fullback to score three tries in a Test against France in the second Test. On 20 July 1988, Jack played for Australia in their record 62-point win over
Papua New Guinea, scoring a
try. After Jack broke an arm in a 1989 pre-season match the door opened for his State of Origin rival Queenslander
Gary Belcher who from that point was the favoured Australian representative for the fullback position. ==Post playing==