Former Wolves captain Mike Bailey has been diagnosed with dementia.
The 78-year-old's family have made his diagnosis public to help highlight the current issues surrounding the disease within football and help support investigations.
Former midfielder Bailey made 436 appearances for Wolves and scored 25 times and is the chairman of the club's Former Players' Association.
Wolves boss Nuno Espirito Santo said: "It's sad news, I haven't had the pleasure of meeting him but we're aware of what he means to the club, a former captain who made so many appearances.
"At the moment he is suffering and fighting against dementia, our thoughts go to him and his family and I know he has the support of the club."
Bailey captained the club when they reached the 1972 UEFA Cup final – losing to Tottenham – and skippered them to their first League Cup triumph two years later.
He also played for and managed for Charlton and won two England caps.
Sir Bobby Charlton was diagnosed with dementia earlier this month while fellow World Cup-winner Nobby Stiles battled the illness before his death in October.
John Richards, former Wolves striker and vice-chairman of the Former Players' Association, told the club's official site: "Mike was a magnificent player and inspirational leader.
"For those of us in Wolves Former Players' Association who played alongside him, and shared a dressing room with him, it was an honour and a privilege. As captain he led the team to some memorable successes, and we know just how loved he is by all of the Wolves fans.
"We share in the sadness that many people will feel that Mike has been diagnosed with dementia and send our love and best wishes to his wife Barbara and the whole Bailey family."