A letter of claim has been sent to World Rugby, the Rugby Football Union and the Welsh Rugby Union by more than 55 amateur rugby players over a potential brain injury lawsuit.
The group includes several retired female internationals, elite male players who took part in the sport before it turned professional in 1995, elite youth-teamers and the family of a male rugby player who died due to chronic traumatic encephalopathy (CTE).
A number of allegations have been raised by the claimants, like the potential negligence of the defendants failing to protect the players from neurological impairments like CTE and early onset dementia.
Their focus is on securing damages for themselves and their families in addition to trying to help change the game to make it safer for future generations.
London-based law firm Rylands Garth are behind the case and already represent more than 275 former professional athletes with brain damage, including England's 2003 World Cup winner Steve Thompson and former Wales captain Ryan Jones, who have issued similar actions against various governing bodies.
Rylands' Richard Boardman said: "It doesn't matter what level of the game you played or are playing at, whether it's at school or adult rugby, and as a professional or amateur, male or female, we are sadly seeing the same alarming neurological impairments at all levels of the game.
"This is a life-and-death issue for many. The vast majority of the current and former players we represent love the game and don't want to see it harmed in any way.
"We now also represent the estates of deceased players who were found to have CTE post-mortem, which is definitive proof that a contact sport was responsible. Those involved just want to make the sport safer so current and future generations don't end up like them.
"This is why the claimants are asking the rugby governing bodies to make a number of immediate changes to save the sport, such as a mandatory limit on contact in training, reducing non-injury substitutions, having a more effective pitch-side diagnostic tool than the HIA, setting up a brain injuries passport, using independent neuro-experts for research and guidance and extending the return to play (following a concussion) to 28 days."
Last September, three former Irish rugby players, two of them ex-internationals, lodged High Court proceedings against the IRFU, World Rugby and their respective former provinces concerning concussion and brain injury.
David Corkery, who represented Ireland 27 times between 1994 and 1999, including at the 1995 World Cup, is taking action against Munster Rugby, the IRFU and World Rugby.
Declan Fitzpatrick, capped seven times for Ireland in 2012 and 2013, is taking a case against Ulster Rugby, the IRFU and World Rugby. The Ulster prop retired in 2015 after suffering a series of concussions.
Ben Marshall represented both Leinster and Connacht before, at 26, announcing his retirement in 2017 on foot of medical advice.
In other news relating to player welfare, the legal tackle height will be lowered to the waist across English community rugby from next season. The radical move has been unanimously approved by Rugby Football Union Council members in an attempt to support player welfare, notably reducing head impact exposure.
It will apply across the community game - clubs, schools, colleges and universities at both age-grade and adult levels - covering the National One division and below in the men's game and Championship One and below in the women's game.
"Designed to improve player safety and informed by data, this change aims to reduce head impact exposure and concussion risk in the tackle for both the ball carrier and tackler," the RFU said, in a statement.
"Evidence from studies has consistently demonstrated that higher contact on the ball-carrier and closer proximity of the ball-carrier and tacklers' heads are associated with larger head impacts (as measured by smart mouthguards) and an increased risk of concussion.