McGrath arrived at Christchurch International Airport on November 29. He was allowed through immigration before being arrested in the city a few hours later, and appeared from custody at the city's district court days later.
McGrath was granted bail and ordered to come back to court today.
His solicitor Phillip Allan told the court this morning that he has filed a notice of opposition to the extradition application.
McGrath now has until January 21 to file his response to the extradition bid, brought by the applicant, the Commonwealth of Australia.
The case will next call at Christchurch District Court on January 28 for an extradition hearing date to be fixed.
Witnesses could come from Australia for the hearing, said Crown prosecutor Mark Zarifeh.
Judge David Saunders remanded McGrath on his existing bail conditions until January 28.
The judge granted in-court media applications to have sound recorded and footage taken of McGrath in the dock.
He explained to Mr Allan, who opposed the application, that he did so after he had concerns that McGrath was "chased down the street" by reporters and photographers at his last hearing.
Mr Allan said the situation was "worse" this morning, which Judge Saunders was dismayed by.
He said McGrath did not deserve that treatment, and said in-court filming was allowed so it could be done in a "dignified and appropriate" manner.
The judge hoped media would take his comments on board.
