So how much did he get? No one is saying - but there is little doubt that the most controversial book of the footballing world will be a bestseller, writes Rosita Boland.

The idea of Roy Keane sitting at a desk in Eason's shop, methodically going through the writer's homework of signing books, is a bit like trying to imagine an uncaged lion scampering through the shop's aisles of provincial newspapers and bestsellers. Yet that is just what Roy Keane will be doing next month.

Keane is the no-frills title of Ireland's most famous footballer's autobiography, co-written with broadcaster and journalist Eamon Dunphy. Having been serialised over three Sundays in the News of the World, it goes on sale this Monday and is predicted to be this year's biggest-selling book in Ireland and the most successful sports book ever. The initial print run is 205,000, with 40,000 copies allocated to Irish bookshops.

Nobody in the business will reveal - on or off the record - how much Keane got for doing this book, or how much Dunphy got. A Sunday newspaper speculated last week that Keane's fee was somewhere in the region of £750,000 sterling, with an additional £250,000 sterling going to Dunphy - which sounds right for this sort of high-profile celebrity sports biography. The figure may have been more, but it was almost certainly not less.

Rowland White is the editorial director of Michael Joseph, an imprint of Penguin which is publishing the book. "I don't think the money he got was an extravagant amount at all," White says. "Given the amount he earns in a week." (The Cork man is believed to take home about £60,000 sterling a week from Manchester United.)

White edited Keane, working on the book throughout the past year. Unlike many books of this ilk, there was no high-profile scramble for the publishing rights at auction, since there was no book on offer as such.

"Every publisher in London would have contacted Michael Kennedy [Keane's solicitor] at some time about a biography from Roy," White says, explaining that this kind of speculative touting is usual in the chase for celebrity biographies. It's a bit like the old Sweepstakes slogan - if you're not in, you can't win. Unless you had your letter in expressing interest in making a pitch for the (then unwritten and unplanned) biography, there was no chance of getting a call when the time came.

In 2000, Keane decided he was ready to tell his story. Penguin made its presentation: the money it would offer, the nuts and bolts of the marketing, the distribution; the works. Penguin won the golden ticket. Dunphy was already on-side from Keane's end. He was clearly going to be chief co-wallah in the whole project from the beginning, no matter who the publishers were.

"Eamon and Roy have worked together very closely since deciding to do the book," White says, conjuring up interesting visions of the two famously acerbic men being polite to each other over computers and dictaphones. One can only wonder at the colour of the air between them when Voldemort himself, He Who Cannot Be Named, was spoken of.

"As an editor, Roy's involvement is very evident to me and that's not always the case with these books. He's read what has been written." Well, one would expect so. "I've worked with Eamon, I've spoken to Roy on occasion, but while it sounds terribly unromantic, for the most time, I've been project-managing the job. Keeping an eye on all aspects of it."

Broadcast interviews this side of the Irish Sea are still being negotiated: who among us is not anticipating what Pat Kenny would make of a Late Late Show interview with Keano? White confirms that "big interviews" with national newspapers in Britain have already been set up, but won't say who they will be with. Given that the serialisation was with the News of the World, a Murdoch-owned paper, it's a safe bet that the interviews will be going to other Murdoch publications.

"The interest in this book has been phenomenal," says Michael McLoughlin of Penguin Ireland. "The phone has not stopped ringing. Everyone wants to know the same things: will he be making any public appearances, and how much did he get paid." Back to the money question: for the record, McLoughlin knows what the money was, but he ain't telling.

Keano's biography was always going to be big, but the World Cup dramas on and off the pitch this summer have added guaranteed sales - both to it and to another imminent football book. Mick McCarthy: Ireland's World Cup 2002, co-written by Cathal Dervan, the Irish editor of Sports.com, will be published by Simon and Schuster/TownHouse in October.

"We were always going to do the World Cup diary," says Treasa Coady, TownHouse's publisher. "But there was an explosion of interest in it after the World Cup. That wouldn't have been the case if the Roy Keane story hadn't happened."

Coady is coy about revealing this book's print-run figures, but does say that "it doubled" as a result of the World Cup dramas. "Booksellers like to have more than one sports book on their shelves. One sells the other," she adds.

Also entering the fray in early October will be Niall Quinn's autobiography, Head First, written by Irish Times journalist Tom Humphries and published by Hodder Headline.

As for Keano's scheduled public appearances, he will be sitting nicely at a table in branches of Easons to sign books in his best scrawl: Cork on September 5th, Dublin on September 6th, and Belfast on September 9th. Keane is published by Michael Joseph (£17.99 sterling)