THE politician to replace violent video game critic Michael Atkinson supports an R18+ classification for games, says a campaigner.

South Australian Premier Mike Rann yesterday said MP John Rau would be the new South Australian Attorney-General after Mr Atkinson stepped down from the position.

In the role, Mr Rau will have input on changes to Australia's classification system — including an R18+ rating for games famously opposed by Mr Atkinson.

Gamers4Croydon party president Chris Prior told news.com.au he had met with Mr Rau and the MP was open to the introduction of an adult rating.

"Just over a week ago, I had the pleasure of meeting him personally when I attended an election forum in his electorate," he said.

"He indicated to me that the lack of an R18+ for games seemed absurd, and that it was really just common sense to introduce it, considering the vast majority of adult content is already available under the MA15+ classification."

Gamers4Croydon ran a candidate against Mr Atkinson in his seat of Croydon in last weekend's state election, on the issue of an R18+ rating.

Mr Atkinson won his seat comfortably but still suffered a swing against him of 14.3 per cent. He resigned from cabinet on Sunday to spend more time with his family and encourage "renewal" in the front bench.

An R18+ rating for games will be on the agenda of the next meeting of attorneys-general in late April.