JON WALTERS had every reason to feel sick on Friday.
As the news broke of Roy Keane's addition to the Martin O'Neill ticket, Walters' memory must have raced back three years to his fall-out with Keane when they were manager and captain respectively of Ipswich Town.
It had been a relationship built on trust until it started to break down over Walters' courtship with Stoke City before deteriorating completely when the Scouser picked up a stomach bug just before a League Cup game in Exeter.
It says much about Walters' state of anxiety that the striker-cum-winger decided "to take a picture of me puke" on his mobile phone and forward it to the club physio as evidence he wasn't pulling a fast one.
Whether Keane believed him or not is neither here nor there. Within a month, Walters was off to the Potteries and speaking candidly about the explosive nature of Keane's managerial style.
"It wouldn't surprise me if some players are terrified of him," said the Irish international in 2010. "In my case, his words went in one ear and out the other.
"You never know where you stand with him and that was the fear factor he brought in. I respected him as a player, but maybe he can't get his point across as a manager.
"There's a way of going about bollocking people. At Ipswich, it became personal a few times."
Damien Delaney, also a former Tractor Boy, was once late to arrive at Ipswich's training ground while Keane was manager there.
Interrupting his progress were members of the local constabulary, who pinned him for driving his Audi A5 sports car at 44mph in a 30mph zone.
After pleading guilty by post to his speeding charge, Delaney then brazenly tried to deflect the blame towards Keane in a letter of mitigation to the magistrates.
"The reason I was going too fast was because I was late for work," Delaney wrote. "I had an unreasonable boss at the time who would not accept lateness and would not have listened to me."
Whether Delaney is ever offered the opportunity to listen to Keane again is one sub-plot to this remarkable story.
Perhaps Stokes, Delaney and Walters should have reacted with caution the way Andy Reid did when he was quizzed about Keane's management after Ellis Short had pulled the plug on the Corkman's time in Sunderland.
"When Roy was here," Reid said in September 2010, "it could be difficult at times but that is probably the same as working for any manager.
"All managers can be harsh at times. All managers can be nice. It probably depends what mood they are in when they come in on the mornings.
"You don't think about managers once they go. The probability is he will never be my manager again."
Now, though, Keane will be O'Neill's assistant manager – a spectacular development for someone who has had such a volatile relationship with the FAI and so many Irish players.
Yet, painting Keane as the bad guy is a cop-out. Those who know him well swear blind by his inherent sense of decency – referring to the stories of his anonymous charity work and the motivational trips he makes to people suffering from serious illnesses, telling them to stay positive and never give up.
Giving up was never a Keane trait. His managerial career may have declined after its spectacular start, and the stories emanating out of Ipswich bore a close resemblance to the ones which followed his Sunderland reign.
Yet, for all the bad signings, tactical mistakes and shabby man-management, there are reasons to believe he can successfully learn under O'Neill's guidance.
"I have got five children and I think I am a better father to my fourth and fifth," said Keane in February last year. "I have learned to be a better husband too.
"I think my driving has improved the longer I have been driving and I think my management will improve the longer I stick at it.
"Will I get an opportunity to get back into it? I don't know. If the opportunity comes along I think I can do well, but because of the way things finished with Ipswich I may have to wait a while, which would be disappointing.
"I have been out of work in terms of a football manager over a year and the longer you are out of it, the harder it is to get back."
Nearly a year and a half after that interview, Keane is back, older – and for everyone's sake – hopefully wiser.
"Playing under Roy Keane is easy," said the Ipswich and former Ireland striker Daryl Murphy. "If you work hard, he praises you. If you don't, you get criticised. He's a fairer man than people give him credit for."
The next two years will prove if Murphy is right. Keane, thanks to O'Neill, has another chance in management. Perhaps his last one.