An upcoming biography of Stan Musial reports that the baseball Hall of Famer has Alzheimer's disease.

In an advance edition of "Stan Musial: An American Life,"  George Vecsey writes

"In his mid-eighties, Musial was diagnosed with Alzheimer's disease. The family pitched in, learned about the illness, tried to keep him as active as possible, to reinforce his contact with the world. From Musial's rare public appearances, people figured out that this merry and decent force in their lives was fading away."

Gerry Musial Ashley, 66, of San Francisco, told the Oakland Tribune this week that "my father has Alzheimer's. A little bit of his personality has disappeared, but he's doing well. He still knows his family."

Biographer George Vecsey is a columnist at The New York Times. Publicity material for the book, scheduled to go on sale May 10, says that Musial, 90, has been "unappreciated" in the past and deserves biographical treatment similar to that accorded Joe DiMaggio. In February, the former Cardinal player received a Presidential Medal of Freedom from President Barack Obama.

Vecsey writes in his book:  “Having covered the deaths of DiMaggio and Williams,I know that Musial’s funeral, whenever it happens, will be far more religious, far more civic, far more loving. St. Louis will get it right. Stan Musial might finally surpass the Clipper and the Kid. Posthumously.”

"Stan Musial" will be published by Ballantine/ESPN. The advance copy is 400 pages. Its price will be $26.