A typically unruffled Warren Mundine was taken aback by his arch rival Fiona Phillips on Tuesday.
"He is a phony and he needs to go back to where he came from," Fiona Phillips told WIN News Illawarra.
The Liberal and Labor candidates have been involved in a public slanging match all week.
Up until January, the Liberal candidate lived in Roseville Chase, and her comment at the Nowra pre-poll booth on Tuesday was not the first time the Shoalhaven-born Labor candidate used her links to the area to favourably compare herself to Mr Mundine.
However, it was the last straw for Mr Mundine, who condemned her rhetoric in a press statement on Wednesday.
"This comment is extremely insulting," Mr Mundine said.
"I'm a member of the Yuin Nation, the traditional owners of the land and sea within the Gilmore electorate. My grandparents were born and married here. My people have lived on Yuin country for thousands of years.
"Like many Aboriginal people, my grandparents and parents often had to move away from their country for work and other reasons. I've had to do the same. I've lived in many places in my life, half of it in regional Australia.
"I now live in Bomaderry. All of that is irrelevant to my status as a member of the Yuin Nation.
"I'm acknowledged as a member of the Yuin Nation under both traditional law and Australian law. In particular, I'm a voting member of the South Coast People native title claimant group whose application is currently before the National Native Title Tribunal.
"No doubt Ms Phillips has given an acknowledgement of country before official events.
"I am one of those traditional owners. Fiona did traditional owners great dishonour and disrespect yesterday by ordering one of them to leave their own country.
"Finally, Gilmore is home to many people who were not born here or don't have ancestors here. All are part of this community.
"I think the people of Gilmore would want more from the person seeking to represent them. No one deserves to be ordered to 'go back to where they came from'."
Ms Phillips stood by her comments on Wednesday afternoon.
"This has nothing to do with land of the Yuin Nation," she said.
"Australia is, and always has been First Nations land.
"Mundine has rolled into town straight from Sydney's leafy North Shore on his big business funded bus."