Alec McNab said the 4x400m Under 18 team had hoped to defend their title, but with several runners out, they had to add an older girl and move up to the Under 20 race, despite two members of the remaining squad being 14 and 15-years-old respectively.
"It's like Steve Hansen losing seven All Blacks."
Sophie Redmayne joined Maples, Williams, and Ana Brabyn to nonetheless win the silver against predominantly older girls.
There was another Women's Relay silver for Osborne, Williams, Maples and Tayla Brunger, along with an Under 20 Men's 4x400m Relay silver from Joseph Sinclair, Travis Bayler, Connor Munro and Jonathan Maples.
Continuing her great championships, Genna Maples won silver in both the Under 18 Women's 100m and 200m, while Ashleigh Alabaster earned silver in the 200m Steeplechase.
Redmayne also won bronze in the Under 20 Women's 400m hurdles, while George Lambert claimed bronze in the Under 18 Men's 2000m Steeplechase.
Munro, Bayler, and Jonathan Maples were part of a composite team that took bronze in the Senior Men's 4x100m Relay.
McNab will have further details in his Athletics Insight column this week.