Tom Magnus grew up in the inner city suburb of Rozelle in the Balmain District. He played C Grade rugby league with the Rozelle Fernleigh Club at sixteen years of age. Tom was called up to trial with the Balmain President’s Cup team in 1927.
He impressed and was selected in a combined junior team that played the Balmain Third Grade before becoming a member of the 1927 Balmain President’s Cup team.
Tom was again selected in the President’s Cup team in 1928. On a tour of the Lithgow district in August, he was described as the outstanding player in the Balmain squad.
He was soon graded and played in the Balmain’s Reserve Grade team that won the 1928 Grand Final.