There are so many misconceptions about Roy Keane the wonder is that the lad can summon the courage to push open his front door in the morning to bring in the milk.

The urban myth has now become the staple diet of your archetypal "shock me, impress me" football supporter, and few players have fed this voracious appetite for scandal and intrigue quite like the soft-spoken 26-year-old from Cork, albeit unwittingly on many occasions.

In many ways the Manchester United player has come to represent the template for the modern midfielder - all mouth and attitude, a terrier-like ball-winner with little regard for his own safety or that of others.

Keane plays his football lost in a red mist, perceiving persecution where, really, there is none, in between picking up causes abandoned by team-mates who are more inclined to bow to the inevitable.

But, lest anyone should forget, the Republic of Ireland international knits together defence and attack better than most. Rather like Newcastle United's David Batty, Keane now represents an enigma, a man out of his time, a throwback to another era when muscle was king and tactics were embraced only by those who did not have the bottle to start an argument. And yet where would United be without him? Perhaps that question should be rephrased: "Where were United without him?"

Last season Keane's campaign lasted only until late September. United's, of course, ran for longer but in his absence it was to yield nothing.

During a Premiership game at Elland Road, Keane spotted Leeds' Alf Inge Haaland dwelling on the ball and decided to act. In a split-second of finely-channelled fury Keane swept away Haaland, the ball and a couple of sods of earth. Unfortunately his standing leg was left embedded in the turf.

It was one skirmish too many and he ruptured a cruciate ligament, an injury which moved Paul Gascoigne and Rangers' Ian Durrant to the brink of early retirement.

The severity of Keane's injury upset some, surprised many but amused even more for as the resident bouncer at English football's most exclusive club, he has few friends outside Old Trafford's Theatre of Dreams.

"He is a great player and there aren't many who could take over from him," said the United manager Alex Ferguson at the time, by way of defending his decision not to seek a replacement.

In the dark days which followed surgery in October, Keane was taunted by seeds of doubt sown in a surprisingly fertile mind and found solace on the bottom of a glass, the injured footballer's best friend.

But even in the world of foaming pints, junk food and fawning hangers-on, where a sense of contentment was just a sip away, there were still problems. This time the demons wore the replica shirts of other teams and many could not resist the temptation to kick while he was down the man they often accused of kicking others as they stood.

"I was naive and probably drank too much," he said. "I used to go to night-clubs, eat too much Kentucky Fried Chicken, have a drink and then people were always ready to have a go at me.

"I used to get into bother. Then everything would get back to the club and get blown out of proportion.

"That's the worst thing about this life - the lack of privacy. But I suppose you should start worrying when people stop coming up to ask for the autographs," he added.

As he attempts to add a philosophical edge to what are infrequent public announcements, Keane insists that with the ageing process and a career-threatening injury has come a serenity, a noticeable maturity.

While not naive enough to discount the possibility of future indiscretions - "I have made mistakes and am sure I will make plenty more" - there is now, perhaps, the realisation that bright stars tend to burn out fastest.

The belief is that Keane may have harnessed the lurking destructive forces in the nick of time. "Now I make sure I know where I am going and who I am going with," he said. "You live and learn. If I was a postman I wouldn't have got into half the trouble I have."

Last week, 10 months after his recklessness had moved him to within touching distance of a scrap heap which boasts the remains of better, more refined players, Keane made his return to senior football.

He played for 45 minutes in a pre-season friendly in Oslo. His knee stood up to the test even if a yellow card suggested his period of enforced contemplation has done nothing to blunt his competitive edge. Hard boys rarely admit to fear but this boy has become a man, and Keane admitted it was a day he feared might never dawn.

"After I had the operation all I could think about was whether I would walk again, let alone play football again," he said. "Playing again seemed a million miles away. To have had to have finished at such a young age would have been very hard to take."

So far Ferguson has declined all invitations to announce that the return to fitness of Keane is - groan - like signing a "new player". He will say it, though. He will have to do so, if only because, though annoyingly trite, it is probably true.

Last season, in those moments when his side's football threatened to unravel at the seams, Ferguson was wily enough not to overplay the Keane factor.

Sure, he dropped his name into those post-defeat speeches which hinted at apology but only the Red Devils' other celebrated enfant terrible, Eric Cantona, has been singled out and placed on a platform for sporting deification since Ferguson began fashioning his Old Trafford dynasty on Bonfire Night 1986.

Barring any 11th-hour hitches Keane will turn out in tomorrow's Charity Shield against Arsenal at Wembley. "I can now see the light at the end of the tunnel," he said.

Whether that light will have a familiar red hue remains to be seen.