[4] Representing New South Wales in the Teal Cup, Brentnall caught the eye of talent scouts from the then struggling South Melbourne Football Club in the Victorian Football League (VFL).
[5] In 2004, Greg was named as a reserve in the Berries to Bulldogs 70 Year Team of Champions.
[6] Brentnall retired from playing after the 1983 NSWRL season at the age of just 26 to take up the position of RL development officer in the Riverina for thirteen years.
[7] Brentnall joined the newly formed Melbourne Storm as assistant coach under former team-mate Chris Anderson.
Later appointed football development manager, he continues to work there and the club have honoured him by naming the young achiever (under 18 player) trophy after him.