Further uncertainty surrounds the South Australian election result with one of two key independents, who will decide who governs for the next four years, taking extended sick leave.

The March 15 poll is set to deliver a hung parliament giving independents Geoff Brock and Bob Such the power to choose whether Labor or the Liberals can form a minority government.

They are yet to make a decision, and Dr Such has now been forced to take extended leave for an undisclosed medical condition.

The situation may complicate the result which is set to deliver Labor 23 seats and the Liberals 22 in the 47-seat House of Assembly.

Labor could govern with just the support of Mr Brock but if he decides to back the Liberals it would leave support for either side in the house tied at 23 votes each.

That could potentially result in a fresh election, though it remains unclear whether Dr Such could still enter into an agreement with either party to give more certainty.

Mr Brock said while the situation was unique, the health and wellbeing of his colleague was his primary concern.

He said he would also seek constitutional advice.

“I’ve never heard of this before,” Mr Brock said.

Premier Jay Weatherill has also expressed concern for Dr Such’s wellbeing and said he had extended his best wishes and support to the MP’s wife.

“We wish Mr Such a speedy recovery and support his family’s request for privacy,” the premier said.

Opposition Leader Steven Marshall wished Dr Such a full and speedy recovery.

“I have spoken with Dr Such’s wife today and offered her and the Such family my full support,” Mr Marshall said.

With the election count to be finalised this weekend, both Dr Such and Mr Brock had been expected to announce who they would support some time in the coming week.

That might now be delayed with Mr Brock saying he is in no hurry to make a decision.

“Bob’s health and wellbeing is the thing that’s on my mind, really, at the moment,” he said.

-AAP