The NRL plans to introduce a watered-down 18th-man policy, allowing for a injury replacement player only when a team has lost three men to concussion.
After a weekend of heightened sensitivity around player welfare amid more than 20 injuries, the players' union has called for a replacement player to be granted as a result of the quickened game.
However the ARL Commission only went part way to that on Tuesday, limiting its use from round five on and ensuring the reserve would only be an emerging player.
Under the rules, Cronulla would have been the only side to have had access to such a player so far this year, when they lost Wade Graham, Will Kennedy and Briton Nikora to concussion over the weekend.
The proposed rule will be discussed with clubs and the Rugby League Players Association before it is introduced, with the NRL to foot the bill of the extra player.
"All fans agree we don't want to see a situation where a club is left with one player on the bench and this rule change will provide insurance for all clubs," ARL Commission chairman Peter V'landys said.
"It will also only be activated in the most dire of circumstances for a club, so we don't see it having a material impact on games every week.
"We see this as an opportunity to give an emerging player a taste of first-grade rugby league in their team's time of need."
The player will also have to be rotated each week, so the same youngster does not miss regular lower-grade games.
The announcement comes after significant debate over any 18th-man rule amid fears it would be exploited.
"With the speed of the game there are going to be unfortunate injuries in the game," Parramatta prop Junior Paulo said.
"I can see ways around it and ways teams will exploit it.
"My opinion is it's unfortunate there are injuries in our game but we play a tough sport so there are always going to be injuries.
One suggestion had been that it could only be used in instances of foul play or potentially while ruling players out of the following week.
The decision to go with three concussions to activate the replacement player at least goes part way to allaying those concerns.
It comes after the AFL introduced a similar rule for all injuries this season, which was used by almost half the teams in the opening round.
"It might be something to protect the integrity of the rule that if you do get subbed off with a concussion that you have to miss the following week," Queensland prop Christian Welch said on Tuesday morning.
NRL boss Andrew Abdo earlier this year ruled out a mandatory period with concerns coaches or players could be deterred from declaring a concussion if it meant they would definitely miss the following match.