Sam Wallace: Keane risks sliding into irrelevanceafter noble decision

The Broadwood Stadium in north Lanarkshire holds around 7,930 supporters and when St Mirren came to visit last month they pulled in as many as 1,904 which counts as a decent little crowd in those parts. Clyde football club are fifth in the Scottish First Division, they have never won a major trophy and in their entire 127-year history, the highlight may be Sunday 8 January 2006: although sadly for Clyde it will have little to do with them.

Roy Keane must have imagined his life after Manchester United many times, but a Scottish FA Cup tie in front of a Cumbernauld crowd smaller than those that watched him train with his former club in the Far East this summer was unlikely to be his first choice. There is no doubt that the prospect of playing for Celtic, the fervour of Celtic Park, the connection with his Irish heritage and the unconditional love of the club's support will have been a powerful influence on his decision, but for a man as addicted to the ideal of excellence he may well be forced to ask himself how much all this matters.

It is a point that is difficult to make without falling prey to allegations of Premiership chauvinism, an argument that tramples dangerously close to delicate national sensitivities but it is difficult to ignore the fact that by choosing Scottish football, a great player, and the end of a great career, threatens to be submerged in irrelevance.

There can be no questioning the depth of tradition at Celtic, or its glorious past, but even the men who run it will admit that if they had to choose a future for their club it would be in the English Premiership and a country where, to be brutally honest, there were more than two clubs that could draw crowds of more than 20,000.

What has appeared to sustain Keane in a profession beset by all manner of absurdity - in its ostentatious trophy presentations, its ludicrous goal celebrations, its vast reward of moderate talent - was a profound belief that what he accomplished, in the Premiership and in Europe, was a matter of sporting excellence. Through all the nonsense, all the excess, he was sustained by a simple principle of achievement. A principle that may be hard to replicate in a proud football nation that has long since been deserted by its best players and managers.

There is something noble about Keane showing faith in a club who have been denied the chance to compete on an equal footing with their English counterparts because of a television deal that is far inferior to the £1.1bn handed to the Premiership every three years although the theory that he is fulfilling a lifelong ambition is a little hard to take. Pushed on the nature of his loyalties to Celtic yesterday, Keane, a man genetically programmed to tell it like it is, resisted any temptation to lapse into a dewy-eyed reminiscence of a boyhood spent dreaming of playing for the club.

Instead, he pointed out that he had first raised the possibility of ending his career at Celtic in an interview in 1999 and that he had been to see games at Celtic Park since then. In fact, it was friends who had loyalties to both United and Celtic who first invited him long after he had moved to Old Trafford. The young Keane supported Tottenham - typically, he has explained, because no one else did in his native Cork - and the player he admired most was also the one he ended up modelling his game on the least: Glenn Hoddle.

Staying in the Premiership would have been a difficult step, given his aversion to ever having to play against United, but a personal preference for Keane would have been for him to take up one of the offers closer to home. The theme of rebellion and non-conformism that has run throughout his career would have been much better suited by a move to Bolton Wanderers or Everton where he would have returned to Old Trafford an unsentimental assassin, unbowed by debt to any former team-mate, supporter or manager.

Only the most marble-hearted United fan would have booed him back into the stadium he did so much to glorify. Instead, he has chosen a different kind of final chapter, one that is, for him, strangely non-confrontational as if, somehow, he has accepted an unspoken responsibility to United not to haunt them. The truth is that he owes them nothing: his only loyalty is to his own unflinching creed of competition.