Also in response to @JohnsonTV.
I’ve found a thesis regarding ABC TV’s role in sport pre and post World Series Cricket. Here’s a table detailing cricket rights holders from 1956 to 1976.
emphasized textEssentially it was a cost saving arrangement but before networking, only The ABC had the capacity to provide a national broadcast.
Fascinating read. The cricket rights are covered from page 22-33 ( of the report not PDF).
