Roy Keane says he turned down the chance to replace Neil Lennon as Celtic boss because the Hoops did not try hard enough to land him.

Parkhead chiefs have always denied making a firm offer but the former Manchester United midfielder insists he was told by Celtic majority shareholder Dermot Desmond the job was his.

However, Keane reveals in his new book how the Scottish champions' take-it-or-leave-it offer left him cold.

The Second Half, Keane's updated autobiography, was due to be released on Thursday, but a Tesco store in Burnage made a huge blunder by putting the books on sale 72 hours early and the contents were published by national newspaper websites soon after.

In the transcripts, the former Ireland skipper says the club's tough negotiating tactics reminded him of the talks when he agreed to sign for Celtic in 2005 as he wound-down the final six months of his playing career.

But ultimately he admits the contract offer - packed full of unappealing clauses and restrictions on the staff he could bring in - "failed to rock my boat".

Keane - whose place in the Celtic dug-out eventually went to Norwegian Ronny Deila - explained: "They were playing the part - 'It's Celtic' - you should almost go up there for nothing.

"Celtic wanted me but they weren't showing how much they wanted me."

The 43-year-old - then working as number two to Republic of Ireland boss Martin O'Neill - adds: "I got a call: would I go and have a chat with Dermot Desmond? I'd met him once before, in 2005, when I was signing to play for Celtic.

"At the end of the chat, he said: 'The job is yours'.

"It was all pretty straightforward. There would be one or two restrictions, about staff. They had already picked the man who would be my assistant and they were insisting on him.

"It didn't scare me off but it did get me thinking. It wasn't an ideal start. Were they doubting me already?

"I came back to the team hotel and spoke to Martin. I told him I would have a think about it. We (the Republic of Ireland) had a game against Italy at Craven Cottage in London on the following Saturday.

"I was delighted. It was a massive compliment. Over the years, I had always said: "If you're offered the Celtic job, you don't turn it down".

"I was in a predicament ... and my gut feeling was saying: 'You're on your own with this one'.

"I asked Paul Gilroy, the League Managers' Association lawyer, to speak to Celtic to discuss terms. Money hadn't been mentioned yet.

"I got in touch with Celtic's chief executive, Peter Lawwell and asked him to give me a ballpark figure before negotiations got going.

"He mentioned a figure and he said: 'But that's it'. Paul told me there were a lot of clauses in the contract that he wasn't happy with. And the figures were non-negotiable.

"I got my head around that. But it felt a bit too familiar. I had been down this road before when I signed for Celtic as a player.

"I felt they wanted me but they weren't showing how much they wanted me.

"We played Italy on the Saturday and I had a message on my phone on Sunday from Dermot Desmond.

"They wanted a heads-up by tomorrow, Monday. I thought about the Celtic offer. It wasn't rocking my boat.

"They weren't convincing me: 'Listen, you're the man for us'.

"I went to Paul Gilroy's house (on Sunday night). There were things I wasn't happy with in the contract. But I know if you examined every clause too carefully, you would never sign anything.

"I rang Dermot on the Monday and said: 'I'm really honoured you offered me the job but I want to stay with Martin'."

Keane is now working as Paul Lambert's assistant at Aston Villa but admits he might have changed his mind on Celtic's offer had they been more accommodating.

He said: "Had Celtic shown enough in their negotiating, 'we'll move this, you can take that' - a bit of give and take - I might have hesitated.

"They just didn't show me that they wanted me and I was happier staying in the Ireland job.

"I felt powerful saying: 'No'. I felt good. But I wondered if I was making the right decision. Right job, wrong time."