The maverick shot-stopper - now a football pundit on Fox Sports - had terrible eating habits and was a late comer to training, according to the Scotsman.
Bosnich went on to be infamously sacked from Chelsea in September 2002 for failing a drugs test, and Ferguson said his initial thoughts were that the Australian international - capped 17 times - was not up to elite standard.
"Mark Bosnich was a terrible professional," Ferguson wrote in the book.
"We played down at Wimbledon and Bosnich was tucking into everything: sandwiches, soups, steaks. He was going through the menu.
"I told him, 'For Christ's sake, Mark, we've got the weight off you. Why are you tucking into all that stuff?'
"We arrived back in Manchester, and Mark was on mobile phone to a Chinese restaurant to order a takeaway.
"Is there no end to you?
"I just couldn't make an impact on him."
The legendary manager, 71, added at the press conference launch that Bosnich did his best to try and end his second United stint before it barely began in 1999.
"Mark got off to a real bad start. He turned up for training three hours late. He was overweight," Ferguson said.
Bosnich had two stints at United under Ferguson, firstly spending time there between 1989 and 1991 before rejoining United for another two years in '99 after seven years of service at Aston Villa.
Sir Alex slams 'terrible professional' Bosnich
