When Niall Quinn appointed Roy Keane as Sunderland manager on August 28th, 2006, it saw one of the greatest midfielders in English football history take the much anticipated step-up into management.
Keane's playing style made him a prime candidate for a managerial future. His skills as captain only furthered his case.
At the time of his arrival, Sunderland were languishing down towards the bottom of the Championship after a short, ill-fated spell in charge for fellow Irishman Quinn, who stepped up to chairman when Keane came in.
He achieved promotion, winning the Championship in his first season, and winning the Manager of the Year award. In his first season back in the Premier League he managed to achieve the foremost goal—avoid relegation.
This season has got off to a tough start, however, and, after a recent poor run of form, Roy Keane left the club on December 4th, 2008.
So where did it all go wrong?
Well, throughout his time as a manager, Keane has had a number of run-ins with people high up in the football hierarchy, most notably the FAI and FIFA Vice President Jack Warner, but this hasn't seemed to affect his job at Sunderland.
He has always kept a relatively cool head in front of the camera as well, a far cry from the Keane of old who once tried to remove Alfe-Inge Haaland's legs from the vicinity of his body.
It seems that he has almost got tired of management. Perhaps it's not quite what he thought it would be.
Keane can be called many things, but a quitter is not one of them, so I doubt that the recent run of poor form is the only reason for his departure. He is notorious for never giving up, so I would have thought he would stick it out as Sunderland manager.
But what seems to be frustrating him most are the performances, rather than the results.
The defence in particular has been a major area for concern for Keane, culminating in the shambolic display against Bolton last weekend. This is something that will be very hard to swallow for a man who was a distinguished defensive midfielder in his day.
But, whatever his reasons for leaving, I think he will regret it in the future. Today's resignation could well have cost him the chance at the seat Sir Alex Ferguson is soon to vacate.