Wayne Bennett has warned the NRL against a one-size-fits-all approach to concussions, questioning if a blanket rule sidelining players for 11 days after a diagnosis is suitable.
The NRL is edging closer towards the next step on concussion management, which could include ruling players out for the following week with no exemptions.
Under current protocols, players are initially ruled out for 11 days after a concussion but can return sooner if given clearance from an independent specialist.
However changes being considered by the league would remove that subjectivity, bringing the game up to speed with protocols in AFL and rugby union.
Bennett, however, is not convinced.
"I wouldn't like to see that go out the door," the Dolphins coach said.
"Some are worse than others. I am qualified enough to tell you that much. I think there needs to be a bit of flexibility there.
"We've got to have a bit of flexibility about whether they should come back on or have lesser days (out of action) depending on the grading of the concussion.
"That's the key to it. Have a grading system and work from there."
Bennett's comments came as Sydney Roosters coach Trent Robinson backed the call for mandatory stand downs, arguing it could only be a good thing for players.
The Roosters have traditionally taken a cautious approach on head knocks, holding back the likes of Boyd Cordner, Jake Friend and Luke Keary in recent years.
Lock Victor Radley has also been ruled out of Saturday's clash with the Warriors with a concussion, after being hurt in last week's loss to the Dolphins.
Robinson said he was unsure what the right answer to concussion management was exactly, but found no issue with erring on the side of caution.
"Time always helps," Robinson said.
"The longer you wait, the better you think it would be. Just naturally we would all think that without us being doctors.
"And the second thing is we actually don't know what happens as well. No one could say they are this much better, or what happens.
"We are not that advanced on the short-term effects of concussions. It's hard to make black-and-white decisions, which is why it has taken so long to put something into place.
"Naturally you would think the longer we would wait the better it would be for the player."
Robinson also stressed it was important any concussion decisions were taken out of players hands to protect them.
"Rads is one of those guys who would play the next day if you gave them the choice," Robinson said.
"He would have played on the Monday if he could have.
"But that's where doctors and then the game comes in to protect him from himself as well."