Three brain injury charities have teamed up to tell the Football Association it must "act now" over funding and the starting of large-scale, independent research into the potential risks of heading the ball.
The joint call from the Child Brain Injury Trust, Headway and The Jeff Astle Foundation follows the publication of new research this week that suggested a possible link between heading a football and dementia, although the study was very small and limited in its findings.
It was, however, only the most recent study of several on sports-related head trauma and the potential development of brain disease in later life, an issue the football authorities have been aware of for at least 15 years.
The FA's head of medicine Dr Charlotte Cowie this week welcomed the latest research and restated the governing body's commitment to finding answers - something the three charities hope happens as a matter of urgency.
In a press release, Headway chief executive Peter McCabe said: "Everyone connected to the game, especially parents, deserves reassurance based on robust evidence that heading a modern, lightweight football is safe.
"At the same time, families of players who were playing in the era of old-style, heavy leather footballs are entitled to answers to the question of whether or not heading those balls contributed to their loved ones developing dementia in later life.
"We urgently need a large-scale project that addresses both aspects of this issue and that builds upon the small-scale studies that have been published to date.
"An independent large-scale scientific study, funded by the FA, must commence immediately.
"If football authorities are serious about protecting those who play and love the game, while encouraging more people to get involved, they must act now."
Lisa Turan, chief executive of the Child Brain Injury Trust, added: "We fully support an immediate call to action of a large-scale evidence based study, which will provide the answers we all need. This way families can be assured of its outcome and be confident with its findings."
Brain disease and football has been an area of concern ever since former England and West Brom striker Jeff Astle died of a degenerative brain disease in 2002, aged 59. A coroner described his illness as an "industrial disease", a reference to his forte of heading the ball.
In 2014, the FA said it was in talks with the Professional Footballers' Association about funding research and had tried to involve football's world governing body FIFA, believing a more international approach would produce the necessary data more quickly.
But those talks came to nothing and last May the FA told Press Association Sport it would press on with British-based research, perhaps in conjunction with other contact sports.
Nine months later, however, there appears to be no news on that front and on Wednesday European football's governing body UEFA announced it was working with an unnamed Premier League club to research the issue.
The slow pace of progress has provoked considerable criticism from what appears to be a growing number of former footballers with dementia and their families.
In response to the new study by Cardiff University and University College London, Jeff Astle's daughter Dawn said: " The evidence is mounting. It is sad to read - I am not surprised, it doesn't shock me at all.
"It's too late for dad. The research is so important for current players and for future players. That's why we need it. I think that's what is so very frustrating - the fact that it's nearly 15 years since my dad died. And the fact that nothing from any footballing authorities has been done.
"It is really indefensible and disgraceful. It really is. This isn't arthritis or a bruised leg or a broken leg. People are dying. This is killing people."
Since Astle's death, a spate of ex-players have come forward with dementia or related problems, including Jack Charlton, Martin Peters, Nobby Stiles and Ray Wilson from England's 1966 World Cup-winning team.
Brain experts have been calling for more research on head injuries and sport for years, particularly in the United States, where heading has been banned for under-11s and American football is just starting to tackle what could be its biggest crisis.
In response to the latest research to come out, Dr Cowie said this week in a statement released by the FA: "In 2015 we established an expert concussion panel which led to the publication of the FA concussion guidelines. These guidelines were designed to help recognise and manage concussion - from the time of injury through to a player's safe return to football.
"The expert panel further agreed that research is particularly required into the issue of whether degenerative brain disease is more common in ex-footballers.
"The FA is determined to support this research and is also committed to ensuring that any research process is independent, robust and thorough, so that when the results emerge, everyone in the game can be confident in its findings.
"To this end, we have recently agreed with the PFA to jointly fund the research project as we believe that a collaborative approach will strengthen the credibility and resource available to the project."