The system -- to be launched by the Australian Rugby Union and effective Saturday across grassroots competitions -- gives the referee full authority to dismiss from the pitch any player showing signs of concussion during a match.
In a game of "more hits, more tackles, more carries and more collisions" -- in the words of former England international Alex Corbisiero -- the recipient of a blue card will not be permitted to return to the pitch for the remainder of the match, and cannot return to rugby until they have passed tests to prove a full recovery.
Affected individuals must undertake the minimum stand down period under ARU guidelines -- 12 days for adults and 19 days for children -- before obtaining professional medical clearance.
Only then will they be able to return.
Rugby's concussion headache
Concussion is a brain injury that results from force either being directly applied to the brain, or transmitted up to the brain as a whiplash effect. In rugby, it can follow anything from a big tackle to an innocuous fall, and can alter -- among other things -- consciousness, memory, mood, or sleep.
A player can be concussed without losing consciousness -- and indeed many such individuals express a desire to continue playing. It is there the danger arises.
Symptoms vary wildly from case to case and often take time to reveal themselves. Premature return can hamper full rehabilitation and put the player under risk of further concussions.
But even at elite level, players have been returning to the pitch despite showing clear warning signs.
George North was allowed to continue earlier this season despite losing consciousness, prompting Barry O'Driscoll
, a leading doctor and former international rugby player, to deem the protocol "not fit for purpose."
World Rugby CEO Brett Gosper told CNN in November that player welfare is the governing body's "No.1 priority," stressing the elite game "has never been safer to play."
Whereas the average concussion assessment of a player during the 2015 Rugby World Cup was 64 seconds and done on-pitch, now the checks are far more rigorous and informed by a video review.
The blue card system represents ARU's intention to tackle the concussion problem head on across all levels of the game and could be rolled out nationwide, according to the organization's chief medical officer Warren McDonald.
"Our concussion guidelines are there to ensure that everyone in our game is educated on how to manage concussion," McDonald said.
"Ultimately the aim is to gather feedback from the upcoming trials and work towards rolling out the Blue Card system nationally across our grassroots competitions at both junior and senior level."
Referees will carry blue cards in the opening round matches of both junior and senior competitions this weekend, kicking off with Saturday's two scheduled first round matches in the ACT's John I Dent Cup.
There are no plans to implement the system at elite level.