In the first legal move of its kind in world rugby, former England international and 2003 World Cup winner Steve Thompson, alongside seven other former players, is preparing a claim against the game's governing bodies for negligence.
Thompson, 42, and the seven ex-professionals - all under the age of 45 - have all been diagnosed as having early onset dementia. The group are claiming rugby union has left them with permanent brain damage.
Their claim is that the governing bodies have failed in their duty of care and are seeking millions of pounds in damages. The letter of claim will be sent to the governing bodies for English and Welsh rugby and World Rugby next week. They are part of the first generation to have played an entire career of rugby union full-time.
Lawyers for the group suggest another 80 former players between the ages of 25 and 55 are showing symptoms.
Thompson, who played 73 times for England and three for the British and Irish Lions, says he cannot remember anything from the 2003 World Cup and is sometimes unable to recall the name of his own wife.
“You see us lifting the World Cup and I can see me there jumping around. But I can’t remember it,” Thompson told The Guardian.
I’d rather have just had a normal life. I’m just normal. Some people go for the big lights, whereas I never wanted that. Would I do it again? No, I wouldn’t. I can’t remember it. I’ve got no feelings about it.
The other players include 41-year-old Alix Popham who was capped 33 times for Wales as a flanker or No 8, and Michael Lipman, 40, who played 10 times for England as a flanker.
Thompson's position as hooker in the front row of the scrum is considered one of the most physically demanding roles in the sport.
World Rugby said in a statement to BBC Sport: "While not commenting on speculation, World Rugby takes player safety very seriously and implements injury-prevention strategies based on the latest available knowledge, research and evidence."