His efforts in Hobart saw him recruited to South Melbourne in 1948 at the age of 21, and after 3 months residency in Melbourne, qualified to transfer leagues making way for his debut on the half back flank against Richmond. He was named best on ground for South's in their match against Footscray. His debut season was solid gaining eight
Brownlow votes. However he suffered a serious knee injury that saw him sidelined for two seasons. Upon return from injury in 1951, the club rested him in the ruck where he shared the position with
Don Scott. However he soon sustained further injuries to his thigh and hand. His return to full fitness saw him take
Ron Clegg's position at Centre half back however it was short lived with recurring injuries seeing him switched to the full back position. His leg injuries eventually put an end to his 1952 season and his VFL career. After years of injury struggles, Dornau resigned from Souths despite being named South's deputy captain in his final season. ==Personal life==