As a lad, McMaster reached the finals of the Australian amateur drumming championships and he was offered a position in a band in Sydney.
But when the young Gordon came home from school and told his father, he was told, in no uncertain terms, that no son of his would be a professional musician.
Instead, he was dispatched to Haddon Rig - one of the leading merino studs in Australia - to work as a jackeroo.
That was followed by stints on various other merino properties, where he worked up through the ranks before starting his own business in 1978.
Two years later, he was awarded a Churchill Fellowship to study overseas developments in the breeding and husbandry of merino and dual-purpose wool and meat sheep, and also trends in the woollen textile industry, which led to trips to South Africa, the United States and Russia.
McMaster's family migrated to Australia in 1834 and he was the fifth generation of his family to have worked on the land.
He was always keen on stud breeding and described merinos as the "aristocrats" of sheep breeds.
In an interview with the Otago Daily Times in 2012, he made no apologies for ruffling a few feathers over the years - "I've said how it is, in my opinion".
His work had been much more than a job - it was a passion and, while he had driven more than five million kilometres, he never got sick of it.
"I don't think I've ever got up and said 'I've got to go to work'."
In January 2009, he was honoured with a Medal of the Order of Australia for services to the merino wool industry and the kelpie working dog industry.
His Wyreema Kelpies stud, which was established in 1882, is the world's longest-established breeder of kelpies.
McMaster was the fourth generation in his family to run it, taking over in 1964.
He exported dogs to Argentina, Uruguay, Brazil, the United States, Switzerland, Russia, South Africa, Germany, Saudi Arabia and New Zealand.
He represented Australia at the Toronto National Exhibition and he also gave demonstrations in the main arena at Sydney Royal Easter Show and at other cities and towns throughout eastern Australia.
He was a foundation and life member of the Working Kelpie Council.