Lawyers for AFLW player Deni Varnhagen want to cross examine South Australia's chief health officer as part of a Supreme Court challenge to the state's COVID-19 vaccination mandate.

The 29-year-old was kept off field and her shifts as a casual registered nurse dried up after she refused to be vaccinated.

The Adelaide Crows midfielder is among a group that has applied to the court to challenge a decision made in March to extend the state's emergency declaration.

Her barrister Simon Owen SC said if the extension was found to be invalid, other decisions to maintain vaccine requirements for public sector employees would also be invalid.

"This case is not a case about the wisdom of the policy about mandatory vaccination for healthcare workers, it's a case about power," he said.

Ms Varnhagen has sought to subpoena South Australian Chief Health Officer Nichola Spurrier and South Australian Police Commissioner Grant Stevens to force them to give evidence.

But lawyers for the government said it was unnecessary for Prof Spurrier to appear as there was other expert evidence.

In response to questions from Justice Judy Hughes about whether it would be appropriate, Mr Owen told the court it was needed to understand what information Prof Spurrier had relied upon.

"I assure your honour the decision to call Prof Spurrier is not to grandstand or to turn the court into some kind of royal commission," the lawyer said.

"That examination would be done with the utmost courtesy."

Justice Hughes is expected to make a ruling on Prof Spurrier's appearance on Thursday.

The decision to impose the mandate for state health workers and other public sector employers was made under the SA Emergency Management Act.

Ms Varnhagen said she had received no nursing shifts since November 2021 after refusing vaccination despite receiving text messages asking for all eligible nursing staff to help fill shortages.

The Crows also shifted Ms Varnhagen to the inactive list after she refused to be vaccinated and she has since been supporting herself by working as a casual labourer "in order to survive".

Ms Varnhagen has been joined in the matter by childcare worker Kylie Dudson, two police officers and another nurse Courtney Millington. However Ms Dudson and the officers are not proceeding with the matter.

Speaking to reporters before court, Ms Varnhagen and her solicitor Loretta Polson said it was unclear whether Mr Stevens would appear as he had "a virus".

"I invite Mr Stevens to take a Panadol and come to court to tell the people of South Australia what information he was given and what information he relied upon when imposing mandates that had the effect of throwing tens of thousands of South Australians out of their jobs," Ms Polson said.

The hearing is due to continue on Thursday.