Back in 2000, in his undoubted prime at the heart of the Manchester United engine room, Roy Keane’s infamous blast at the Theatre of Dreams’ ‘prawn sandwich brigade’ sprang up headlines nationwide.

The tough-tackling Irishman, not shy of controversy and prone to speaking his mind, suggested that “some of the people who come to Old Trafford can't spell 'football', never mind understand it.”

Fast forward eight years, and the irony is harder to ignore than a chorus of ‘Blue Moon’ over Old Trafford’s tannoy system. Keane is once again cast into footballing wilderness, resigning in a blaze of inconsistency after his Sunderland side languished in the Premier League table.

It seems that it takes more than the ability to spell ‘football’ to have the ability to play it – more so, the ability to manage a bunch of Sunderland players suspiciously out of their depth.

Keane’s multi-million pound squad makeover was the equivalent of tarting up a hobo with a Harrods shopping spree – the aesthetics may be improved significantly, and his contemporaries would no doubt sit up and take notice, but deep down the same old problems are engrained within the fabric.

However, it seems unconceivable that one of the brightest young managerial talents in the United Kingdom would be under such intense pressure due to on-field problems – the nature of the top-flight this season means back-to-back victories can propel a relegation-threatened club into mid-table. More likely, Keane is a victim of his own success.

Thrust into the limelight after masterminding a ‘turnaround’ of Bonnie Tyler proportions, all ‘bright eyes’ were on the Irishman as he took the Black Cats from rock bottom of the Coca-Cola Championship to the riches and prestige of the Barclays Premier League in just one season. The bright lights of the world’s best and richest league illuminated the Stadium of Light - and Keane was once again back where he belonged, on centre stage.

Talk of Keane inheriting the throne at Old Trafford naturally surfaced, and the parallels with his managerial ‘godfather’, Sir Alex Ferguson, were unignorable. Keane was Ferguson’s natural heir, many claimed. His protégé, destined to return to his spiritual Old Trafford home in a blaze of glory. As close to a footballing fantasy as possible but, as Kevin Keegan will no doubt testify, fairytales are exactly that the majority of the time.

Much is made of the story about Ferguson coming within 20 minutes of the axe, before Mark Robins netted the winner against Nottingham Forest in an FA Cup tie and the rest, as they say, is history.

Times were undoubtedly hard for Fergie in his early years in Lancashire, but what was his response? To first of all save his job and then build an empire, to such an extent that the worldwide Manchester United brand will forever be associated with him in the eyes of many Mancunians.

One must sense that Keane would have been best served doing something much the same – riding out the inevitable rough waters encountered by many young managers and using the experience to their advantage. But it is all too easy to suspect that Keane’s ego was his undoing. There can be little doubt that he is a born winner - second best meant nothing, and so he was never likely to be content with his charge’s indifferent form.

But amongst the stories about Keane’s bi-polar personality with his players and a tense relationship with chairman Niall Quinn, there was a refreshing air about Roy's managerial bow. In a time when football success is measured by Chryslers and mansions rather than clean sheets and man-of-the-match appearances, Keane appeared genuinely different. He represented a throwback to a time when football was played with spirit and passion, rather than as a part-time pastime with next week’s bumper pay cheque in mind.

A heart-on-sleeve attitude on the playing side of the white touchline transferred to the dugout side, and Keane appeared to strike a perfect balance between head and heart, guile and graft. Bustling with magnetism and appeal, even die-hard anti-Manchester United supporters found it hard to begrudge Keane’s meteoric rise to prominence.

Something always appeared to be missing, however. Much like a carpenter equipped without the use of a hammer, Keane’s Sunderland squad never threatened to make the next step up - and were never likely to do, despite all of Quinn’s millions thrown about like confetti.

The man himself alluded to these struggles in a terse statement issued after his divorce from the North-East club, insisting he has “enjoyed the rigours of being a manager.”

“I look forward to building on those experiences and sometime in the future returning to football management,” Keane insisted.

With the greatest respect for the perhaps aptly-named Black Cats, one can only assume that a higher calibre of players and perhaps ambition to match Keane’s will bring out the best in a character who has promised much but, in the grand scheme of football management, delivered little.

Where his next challenge will come from, and whether it will one day enable his name to be hailed once more by the Stretford End, remains to be seen. But, what is for sure is that a character as complex and attention-courting as Keane is unlikely to fade away from the footballing spotlight without further controversy. He will be back.