[1] Colvin was first selected to cox the Victorian men's eight contesting the 1985 King's Cup at the Interstate Regatta within the Australian Rowing Championships.

Consequently of the twelve times he contested the event, Colvin steered ten Victorian eights to King's Cup victory.

[1] Colvin made his Australian representative debut in a coxed four at the 1990 World Rowing Championships in Lake Barrington, Tasmania.

In 1995 Colvin was again in a national representative boat steering the men's coxed four who finished in fifth place at the 1995 World Rowing Championships in Tampere.

As an Australian Institute of Sport selection eight they contested and won the 1997 Grand Challenge Cup at the Henley Royal Regatta.