Verdonk began rowing at
Westlake Boys High School in
Forrest Hill,
Auckland. In 1976, he won the
Maadi Cup. He was a member of the
North Shore Rowing Club, joining the club in 1973. the race was won by
Steve Redgrave. and finished third in the final In total, he competed at five
World Rowing Championships, and his best result was third, at the
1990 in
Tasmania, Australia. Verdonk was sixth in the single sculls at the
1987 World Rowing Championships in
Copenhagen, and was fifth in the single sculls at the
1991 World Rowing Championships in
Vienna. In 1994, Verdonk won the
double sculls event at the Commonwealth Championships in
Ontario, Canada, and finished second in the
quad scull event. Verdonk also won the
Diamond Challenge Sculls (the premier singles sculls event) at the
Henley Royal Regatta, becoming the first New Zealander to win the event. Another year, Verdonk came second in the single sculls event at the Henley Royal Regatta. He won seven consecutive New Zealand single skulls national championships between 1987 and 1993. He won six New Zealand double skulls national championships, with four different partners. Following his retirement, Verdonk worked for
Waitakere Sports Association, and from 2017, Verdonk was the head coach at Takapuna Grammar School Rowing Club In March 2020, the club made him a lifetime member. Also in 2020, the
New Zealand Rowing Foundation awarded Verdonk a legacy medal for his contributions to rowing in New Zealand. ==Personal life and death==