The father-of-four said he was missing his family, but he was also missing the high standards he has grown accustomed to as captain of Manchester United.
Keane is used to the luxuries of life.
As a United star, he is lavished; as a member of the Irish squad, he felt he was ridiculed.
"The hotel is fine, but we've come here to work.
"I can't imagine any other country in the world who are far worse
off than us, playing on something like that.
"But we're the Irish team, it's a laugh and a
joke. We shouldn't expect too much."
You will not find a harder competitor in a game than Keane, and he expected the same attitude from his team-mates, even in training.
When the goalkeepers were told they need not take part in a training game because of tiredness earlier this week, Keane flipped his lid.
"I did mention that they wouldn't be too tired to play golf the next day and, fair
play, they dragged themselves out!"
Playing on a pitch he described as "like a car park", Keane refused to add injury to insult.
Keane's high standards
He retired from international football with immediate effect, although a good night's sleep and a telephone call home at least persuaded him to defer his decision until after the World Cup.
But that was before the Football Association of Ireland stepped in.
The fact that no-one lives up to Keane's high standards is reflected in the fact that the captain roomed on his own with Ireland.
But he did not sit in a leather armchair, sipping champagne and having grapes peeled and fed to him.
Keane likes the simple things, explaining: "I prefer to be on my own as regards using the telephone, getting up, reading, using the bath, whatever you might want.
Reflective time, if you like.
Perhaps Keane may yet reflect on the folly of his ways costing him the last chance to perform on the world's greatest stage.