Mick McCarthy refuses to confirm if the subject of Roy Keane returning in time for the World Cup finals next year was broached in a telephone conversation with the stricken Manchester United player at the weekend.

Neither does he deny it. Beyond saying that the player was very positive in his attitude after being told that he must undergo surgery for the repair of a torn cruciate ligament, the Ireland manager was not commenting on what he termed a courtesy call.

Yet, even before the player enters hospital for an operation later in the month, there is widespread speculation that he could be fully fit again before the end of the season. And in the event of Ireland emerging unscathed from their imminent World Cup play-off, that could mean a coveted working assignment in France in the summer.

Some of those predicting an earlier than scheduled re-appearance for Keane speak from deep experience, none more so than Niall Quinn, his team-mate in some memorable Ireland performances over the last seven years.

Quinn has been through the trauma of football's worst injury on two occasions. In the first instance, he damaged his knee in a club game in November 1993 and didn't play again until the start of the '94-'95 season.

With the benefit of experience and far fewer complications in the initial stages of his recuperation, he was back in full training considerably quicker on the second occasion after severing the cruciate ligament in his other knee last September.

Unfortunately, a knee problem is currently keeping him out of the Ireland and Sunderland teams, but he denies emphatically that it is a residue of the original injury or that the second operation was not wholly successful.

His biggest regret remains that his club refused him permission to play in the 1994 World Cup finals in the United States at a stage when he believes he was perfectly fit. The same ordeal, if not necessarily the same judgment, awaits Keane if his surgery proves successful.

In the context of getting ready for next year's World Cup finals, he has a two-month start on Quinn, back in 1993, and with the evolution of medical science and the case history of others to guide him, it is not unreasonable to assume that he will beat the deadline.

His great problem, as Quinn discovered four years ago, will be to persuade Alex Ferguson that he is not putting his long-term career at risk by coming back from the most dreaded of all injuries to play in the most competitive of all championships.

Brian Horton, the then Manchester City manager, apparently decided that Quinn's own judgment on the extent of his recovery couldn't be trusted. And in spite of nominating him to succeed Eric Cantona as team captain at the start of the season, it remains to be seen if Ferguson's decision will be any less disappointing if he is asked to rule on an earlier than scheduled return by Keane. Reflecting on the latest injury problem to hit his squad, Ferguson, who is due to receive an honorary degree from Manchester University tomorrow, voiced the feelings of many when he expressed alarm at the growing number of players who have torn cruciate ligaments.

Knee injuries are nothing new in football, but the increasing incidence of damaged cruciate ligaments is disturbing. There is little doubt that the growing demands on players and heavier workloads are responsible in part for the increase.

The Manchester United manager has another theory and it concerns the kind of boot studs now in use. Keane's injury came not primarily from making contact with another player, but apparently because the studs on the boot of his "standing" foot became trapped in the ground causing his knee to wrench.

As a result, Ferguson has now banned screw-in studs from the club's training ground.

In the meantime, Keane is left to rue the consequences of one skirmish too many. Some of the statements made in the wake of the news that he had sustained a serious injury were, to say the least, uncharitable and may have been motivated by other agendas.

In the course of an eventful career, he has brushed with disturbing regularity with match officials, media personnel and, not least, fellow professionals. Yet, it ought not obscure the fact that in an age when the physical demands of the game are quite intense, his is a special talent.

That has long been recognised by Manchester United, but there were occasions, several occasions in the early phase of his Ireland career, when he was markedly less imposing in international football. That was possibly a consequence of the game plan he was asked to implement during the Jack Charlton era, but whatever the reason, he has been significantly more successful since making his peace with Mick McCarthy and returning to the international squad almost a year ago.

To that extent, the timing of his injury is at best unfortunate, but for all the reservations being voiced at Old Trafford, it is still possible that if Ireland survive the play-offs, he will again have the opportunity of playing on the biggest stage of all in France.