SA Liberals reshuffle front bench

South Australian Opposition Leader Steven Marshall has reshuffled his front bench to deliver what he says is a sharper focus on the state's unemployment woes.

There are no new faces in the line-up, with the key changes including David Pisoni moving to transport and infrastructure, Corey Wingard to employment and John Gardner to education.

Deputy leader Vickie Chapman also takes on added responsibilities including state development.

"I'm confident these changes will result in even greater scrutiny on the failings of the floundering government," Mr Marshall said on Wednesday.

"The changes in portfolio responsibilities will deliver a shadow ministry with a sharper focus on combating South Australia's unemployment crisis through substantive economic policy development."

The Liberal reshuffle comes ahead of one planned by Premier Jay Weatherill.

The premier will announce his revised cabinet before parliament resumes next month with new MP and former union boss Peter Malinauskas certain to be included.

The premier's ability to make changes was made easier on Tuesday when Emergency Services Minister Tony Piccolo moved to quit his post and head to the back bench.

Mr Marshall's changes also come as a Newspoll puts support for the Liberals on the rise with its primary vote up five percentage points to 38 per cent.

But the opposition still trails Labor on a two-party preferred basis 51-49 per cent.