Former England international Chris Sutton has accused Professional Footballers' Association chief Gordon Taylor of letting players down after a landmark study showing the link between football and dementia.
A Glasgow University study found former footballers are approximately three-and-a-half times more likely to die from neurodegenerative diseases than the general population.
The report, released on Monday, was commissioned by England's Football Association and the PFA and assessed the medical records of 7,676 men who played professional football in Scotland between 1900 and 1976.
Outgoing PFA chief executive Taylor has been strongly criticised for his lack of action on the subject, in particular by the family of former West Bromwich Albion striker Jeff Astle, whose 2002 death from chronic traumatic encephalopathy (CTE) was linked to repeatedly heading heavy leather footballs.
"The confirmation that there is a link between football and dementia brings me no satisfaction. It makes me angry," Sutton said in a column in the Daily Mail newspaper.
"Angry for people like my dad, Mike, and other former footballers who are dying in the most horrible and humiliating way. Angry for the future generations who will suffer, too, because this study was rolled out 15 years too late."
Sutton said a study should have been commissioned in 2002 after Astle's death.
"The PFA, led by Gordon Taylor, had a duty of care to their members," Sutton said. "They let them down."
He added: "My dad, a former Norwich player, is suffering from chronic traumatic encephalopathy - a degenerative disease of the brain caused by repetitive brain trauma. He is 75 and first developed symptoms of dementia when he was still in his sixties."
Jeff Astle's daughter, Dawn, who has been campaigning since her father's death for football to research into the area, said she was "staggered" to learn of the findings.
"My overall feeling is that I am staggered even though my own research and instinct was always that there was a serious problem," she said.
"There will be no celebrations. It doesn't bring my dad back, it won't bring any other dads and husbands back.
"We knew dad could not be the only one. We just wanted that question answered."