The family of former England striker Jeff Astle – whose death was directly attributed to degenerative brain disease caused by heading footballs – claim to know of around 250 other ex-players who have lived with similar conditions.
After it was recently revealed that three members of England's 1966 World Cup-winning squad have been diagnosed with dementia, Astle's daughter Dawn has spoken about her family's fight to highlight the link between multiple, minor brain traumas from repeated headers and degenerative brain disease in later life. Since starting the Justice for Jeff campaign in April 2014, Dawn has pushed for independent research into brain injuries in sport and the resulting development of Alzheimer's, dementia and other neurodegenerative diseases.
The FA now wants FIFA to investigate a possible link between dementia and football. However, they have been slow to react.
"Any research and study done into the possible implications of heading footballs clearly has to be a good thing," Dawn told the BBC.
"But they could have done all this 14 years ago, when they had the coroner's verdict for my dad. 14 years is a damn long time."
Jeff Astle died in 2002 at only 59 years of age, after choking on a piece of food. He had been diagnosed with early onset Alzheimer's and his brain condition was directly associated with the manner of his death. An immediate inquest found that repeatedly heading heavy leather footballs during his career had caused trauma to his brain. The coroner recorded a verdict of death by industrial disease.
Though he had been diagnosed with Alzheimer's, a doctor who examined his preserved brain in 2014 said he actually had chronic traumatic encephalopathy (CTE). More commonly found in boxers and American footballers, the condition is attributed to severe blows to the head.
Since 2014, Dawn Astle has been contacted by families of numerous other footballers affected by degenerative brain disease. "There's got to be about 250 [former players] that I know of. Not all of the families have come forward and some of the players have passed away," she said.
In light of the admissions about the 1966 World Cup winners, she said: "It's great that these iconic players and legends in the game have come out, very bravely, and their families have spoken about the suffering they are in now, but it doesn't just affect household names.
"We've had contact from many, many players, many of whom I'd never heard of, but they all matter. I think it is the tip of a very big iceberg, sadly. I wish it wasn't, but I think it is."
Astle's family have said that they have been told about players suffering with degenerative brain disease by fans and people associated with football clubs, too. Astle himself made several hundred appearances for Notts County and West Brom between 1959 and 1974.
Dawn went on to say that around 95% of the former players affected have suffered from Alzheimer's disease, while the rest have had other degenerative brain diseases. Though Jeff Astle's generation played with heavy leather footballs, Dawn is still worried for those currently playing the game.
"How it was described to me is the balls nowadays are much lighter but they travel faster, and sometimes players are much stronger and hit it harder," she said.
"It's down to the pure physics of something striking the head and the brain being rocked backwards and forwards in the skull. I hope to God that there isn't a link with the modern day ball but I would be very, very surprised if the safety implications aren't the same."
Having also formed the Jeff Astle Foundation in 2015, Astle's family want to raise awareness of brain injuries in all sports, secure independent research on degenerative brain disease and provide support for sports people living with dementia or chronic neurological impairment. Though Dawn has said her father would not have wanted heading in football to be banned, the Foundation want players to be able to make an informed choice.