Former Howard Government minister, Alexander Downer yesterday reportedly told the party they would be punished at the March 2010 election should they be unable to sort through inner party tensions.

The comments come after South Australian Opposition Leader Martin Hamilton-Smith called an extraordinary joint parliamentary party meeting for Saturday, to decide his future amid growing dissent among Liberals over his performance.

He will be challenged by current deputy Vickie Chapman who, within minutes of Mr Hamilton-Smith announcing the meeting, declared her intention to run for leader.

"Whether they like Martin Hamilton-Smith or whether they like Vickie Chapman, this isn't Hollywood ... this is about the government of this state," Mr Downer, who is now the chief fundraiser for the party's upcoming election, told Ten News.

"After Saturday - no further discussions about the Leader, no background briefing to the media about how they don't like the leader."

State opposition front bencher Isobelle Redmond put an end to speculation surrounding her support for Ms Chapman, saying she would stand for the deputy position on Saturday should Mr Hamilton-Smith be re-elected to lead the team.

"I won't be putting my hat in the ring for deputy if Vicki becomes the leader," she told Ten News.