The AFL season is in serious jeopardy with South Australia set to shut their borders from 4pm Tuesday.

People arriving after that time would have to self quarantine for 14 days, meaning Port Adelaide and Adelaide could not host games or return from interstate and play.

It comes after Prime Minister Scott Morrison recommended all non-essential travel be cancelled.

It is unclear what these new jurisdictions mean for the AFL, but it is now unlikely that the competition will proceed with round two.