After doing more than most to bring the Republic of Ireland to the World Cup in 2002, Roy Keane was unhappy with the team's preparations, in particular their training pitch in Saipan, an island the team stopped at on their way to Japan/Korea.
After Keane criticised the training facilities publicly, manager Mick McCarthy was understandably unhappy and the result was a fall-out between the two only days before the start of the tournament.
McCarthy, who bore the brunt of an expletive-ridden rant in front of the squad, later said: 'I have never witnessed such an attack from any human being. It was vicious and it was unjust.'
Keane was sent home before the finals began and the country was split in two. Attempts were made to pave the way for Keane to return to the squad but the damage was done and Ireland's most influential player stuck to his principles and missed the chance to appear in what would have been his last World Cup.
However, the episode did force the FAI to take a look at their procedures - with many of Keane's gripes being investigated by the Genesis report - a report that was launched by the FAI to ensure future practices and preparations were of a standard expected by a professional outfit.