Clubs face the loss of competition points, and trainers possible suspension from the game if they flout the NRL's new stringent concussion laws.
NRL head of football Todd Greenberg outlined the tough new sanctions at a media briefing on Thursday.
The game's governing body had previously flagged significant changes to the way clubs need to assess players who appear concussed.
They've now handed down a series of possible sanctions in a warning to all clubs ahead of the season start next week.
"This is a very important change in policy and clubs need to understand the gravity of that," Greenberg said.
"Rugby league is a very tough sport but player health and welfare is at the forefront of every decision we make.
"Clubs need to understand these are very serious issues."
Under the new concussion rules a potentially concussed player must be diagnosed by the head trainer, and then if warranted assessed by the club medical doctor, who will determine if he is fit to return to the field. If, according to a series of tests, he is not fit to return, the new rules deem any contravention of that illegal.
If clubs flout the new rules and a concussed player returns to the action, Greenberg outlined a number of possible sanctions which included:
* the loss of competition points;
* a substantial fine; and
* suspension of registration of club personnel.
Greenberg said if a coach, trainer and club doctor are all found in collusion they could all face sanction.
"It would be a very brave coach who puts his position on the line to gain a tactical advantage (by flouting the rules)," Greenberg said.
"I have made that very clear.
"These changes are for the good of the game.
"The gravity and seriousness of the situation must be understood."
The new NRL governing concussion come into play when the season starts on March 6 between the Sydney Roosters and South Sydney.