But worse was soon to come after a training ground bust-up involving Keane, assistant boss Carlos Queiroz, goalkeeper Edwin van der Sar and Ferguson. Keane reveals he said to Ferguson: 'You as well gaffer. We need f****** more from you. We need a bit more, gaffer. We're slipping behind other teams.'
Keane later met Ferguson to discuss why he had been left out of a reserve match, which had been pencilled in to help his recovery from a broken foot, but was shocked at how the meeting unfolded.
He reveals: 'Fergie said: 'Roy, I think we've come to the end? before chief executive David Gill presented a written statement on the Irishman's departure. Keane said: 'They had it all ready. It was another little hand grenade they threw at me. Not an hour later, or two hours, or after the severance negotiations - it was already written. I said to Ferguson 'Can I play for somebody else? And he said, 'Yeah you can, cos we're tearing up your contract.' So I thought, 'All right - I'll get fixed up'.
I knew there'd be clubs in for me when the news got out. I said, 'Yeah - I think we have come to the end'. 'I just thought, 'F******' p****' and I stood up and went 'Yeah. I'm off'. Keane, who agreed to leave that day, also reveals his exit cost him 1million - a bonus written into his contract if he played in 50 per cent of United's matches that season.
Almost a decade on, he now regrets apologising to Fergie and Queiroz (right) after the bust-up. 'Now I kind of wish I hadn't,' he writes.
'Afterwards I was thinking 'I'm not sure why I f****** apologised'. 'I just wanted to do the right thing. I was apologising for what had happened - that it had happened. But I wasn't apologising for my behaviour or stance. There is a difference. I had nothing to apologise for.
In his own book, released last year, Ferguson said his former captain had 'overstepped the mark' and when questioned at the time, Keane said he would deal with the 'lies' on another occasion.
In Keane's latest book - which follows his first edition of more than a decade ago - he reveals that he cried in the car for two minutes after the meeting with Ferguson and Gill and accuses them of 'getting the length of his service wrong in the initial statement.
When he pointed out that he had been at the club twelve-and-a-half years, one of Ferguson or Gill said: 'Was it '93 when you came in then?' and Keane replied: 'Yeh.
The first year we won the double. 'Later in the book, Keane reveals his ongoing irritation at the way he feels he was portrayed in the wake of his departure. He believes the club were happy for him to be lampooned as a 'head case'.
Claiming that he had offers from Real Madrid and Everton after his departure, Keane eventually joined Celtic for just 15,000-a-week. Despite the fact Ferguson signed Keane from Nottingham Forest in 1993 and the two men eventually won seven Premier League titles, four FA Cups and a Champions League together, the pair have never reconciled their differences since that day nine years ago. And Keane also reveals that Ferguson would go for two weeks at a time not talking to him if he thought he had played an unnecessary international or risked his fitness.
'It was childish,' says Keane. 'It happened regularly. 'In his book, Keane reveals controversially that he made money out of the Glazer takeover of United. 'I had a few shares so the Glazers coming in was worth a few bob,' he says. The midfielder claims Ferguson did not want to give David Beckham the iconic United No 7 shirt, offering it instead to Keane. Keane says he turned it down and Ferguson declared: 'I know Becks will f****** want it and I don't want him to have it. It is clear, also, that Keane believes his former manager should never had got involved in the row over Rock of Gibraltar that preceded the two Irish owners - Magnier and McManus - selling their majority United shareholding to the Glazers.
Keane has hinted at this before and says in his book: 'He (Ferguson) was just a mascot for them - 'look at me, how big I am' - and he didn't even own the bloody thing.
Keane adds that he had been told by someone in Ireland to advise Ferguson to drop the fight but that he wouldn't listen.
Throughout the book, Keane is actually extremely complimentary about Ferguson, describing how he must have listened to more than 500 team talks during his time at United and never once got bored. He describes some of his motivational work as 'amazing' and admits that he has tried to copy it at times during his own managerial career at Sunderland and then Ipswich.
However, he claims that his manager at Nottingham Forest Brian Clough was superior to the man he won most of his medals with. 'I put Brian Clough ahead of Alex Ferguson,' he writes.
'I think with Sir Alex Ferguson it was pure business - everything is business. If he was being nice I would think: 'This is business, this'.
He was driven and ruthless. That lack of warmth was his strength.' Although Keane's relationship with Ferguson had been good for many years, it is clear he had not got on with assistant Queiroz, who had two spells at the club.
The two men clashed over what Keane thought were repetitive training sessions and over facilities on a pre-season training camp in Portugal.
According to Keane, Queiroz questioned his loyalty to team-mates and Keane replied: 'Don't you f****** talk to me about loyalty, Carlos. You left this club after 12 months a few years ago for the Real Madrid job.'
During the discussion about training methods, Keane admits he suggested to the assistant manager that he wouldn't make love to his wife the same way every time and asked why he would be so repetitive in training.
-By Ian Ladyman of the Daily Mail.
