Cricket Australia said Wednesday it will trial injury substitutes in this season's domestic Sheffield Shield to determine whether it is feasible to introduce at Test level.
The trial, with International Cricket Council approval, will be conducted over the opening five rounds of the red-ball competition, which gets under way this weekend.
Teams will be able to replace an injured player up until stumps on day two, at the match referee's discretion.
In the interests of fairness, the opposition will be able to make a tactical substitution in response, within the same timeframe.
There are no restrictions on the type of ailment, and the injury may be sustained any time after the toss, either pre- or post-play, Cricket Australia said.
This goes further than a version implemented in India this year.
Under the Indian model, the injury has to have happened during the game and needs to be external -- like a deep cut or fracture -- rather than internal, such as a hamstring strain.
"At and before the conclusion of round five, CA management will be collecting information on the success or otherwise of the trial to assess the options post that round," said Peter Roach, CA's head of operations.
"We hope to learn much about the trial across the first five rounds that we can use in both our competition going forward, and also pass up to the ICC for consideration for introduction at Test level."