They've became the most unlikely love story in modern times. When Martin O'Neill announced that he was appointing Roy Keane as his assistant when he took over the Ireland job, many sceptics raised an eyebrow.
Keane is portrayed as a type of cartoon character; always blowing his top and having to clean up the consequences whereas O'Neill is seen as one of the Crane brothers from Frasier (mainly because of the fact that he studied law at Queens University for a while).
But the two share an undoubted fondness for each other. Whatever you say about Roy Keane, nobody can doubt the fact that his joy at Ireland's achievements last night was genuine. He'd be the last man on earth to fake that sort of emotion. There's a bond there between the two men and it's fascinating to see it develop.
O'Neill was in predictably cracking form in today's press conference and the topic of Keane's beard soon came to the fore - particularly after the pair's embrace after the winner last night.
"I told [Roy] to shave his beard. It was rustling my chin and I don’t want him to hug me again ever.
He said: ‘You are an ugly sod’ and I agreed wholeheartedly. I then retorted and said he wasn’t Paul Newman either.
We were delighted to win the game and be part of that evening and it was genuinely special. We felt that we were part of that evening, one not to be forgotten. To see the fans enjoy it, it more than made up for the Belgium game. Last night, players and fans together fused in a way that they kept each other going."