England World Cup winner Nobby Stiles died with a brain condition caused by repeatedly heading a football, a coroner ruled.
Stiles, who died aged 78 in October 2020, had headed a football around 140,000 times during his career, Stockport Coroner's Court heard at the inquest into his death.
The hearing was told the former Manchester United footballer died with severe dementia, with expert analysis of his brain showing it was as a result of Alzheimer's disease but also chronic traumatic encephalopathy (CTE), which has been associated with head trauma from heading a ball.
Neuro-pathology expert, Dr Daniel Du Plessis told the court: "I'm quite convinced his heading the football that many times has caused his CTE."
Alison Mutch, senior coroner for South Manchester, asked Dr Du Plessis: "You are saying repeated heading of the ball is the cause of his CTE?" Dr Du Plessis replied: "Yes."
Stiles was best-known for being one of the key members of the 1966 England World Cup winning team.
He died in October 2020 after a long illness in which he was diagnosed with dementia and suffered a mini-stroke in 2010.
His family has since campaigned for football authorities to better support ex-players.
Stiles' son John has previously said that football had "killed" his father.
He was capped 28 times by England and made nearly 400 appearances for Manchester United, but was forced to sell his medals to fund his dementia care.
Last Friday, Chris Morris, area coroner for Greater Manchester South, told Stockport Coroner's Court neuropathology expert, Dr Daniel du Plessis, had examined samples and medical records and due to the injury a full inquest into his death was required.
Mr Morris said "for reasons not entirely clear to me" Stiles's death was not at the time reported to the coroner's office for investigation, which had only begun after information provided by the ex-footballer's family.
He added Dr Du Plessis had determined Stiles's cause of death as Alzheimers disease.
But he also said his death was contributed to by high-stage CTE.
Mr Morris continued: "On the basis of that cause of death, particularly the inclusion of a traumatic injury included in the cause of death, I'm satisfied an inquest is required into the sad death of Mr Stiles."
John Stiles, head of the Football Families for Justice (FFJ) group, is among dozens of former footballers and their families suing the Football Association, the Football Association of Wales and the English Football League.
They claim football's governing bodies were "negligent and in breach of their duty of care" to the former players.
Read more from Sky News:
Did football fail Nobby Stiles?
Can there be 'too much football'?
In March this year, lawyers for The Football Association told the High Court it has "not been established by science" that heading a ball or "occasional" concussion can lead to permanent brain damage.
A study in 2019, co-funded by the FA and Professional Footballers' Association (PFA), found footballers were three-and-a-half times more likely to die of neurodegenerative disease than age-matched members of the general population.
The FA is phasing out all heading in youth football up to under-11s by 2026.
(c) Sky News 2026: England World Cup winner Nobby Stiles died with brain condition caused by repe
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