Sir Alex Ferguson has described his 25 years at the helm of Manchester United as "a fairytale". Ferguson will celebrate a quarter of a century in the Old Trafford hotseat on Sunday. It is a quite incredible achievement at that level of the game, testament to the astonishing success he has brought to United. Although there have been a number of presentations over the past few months, Ferguson has never given the impression of being entirely comfortable discussing past glories. Even on Thursday, when quizzed about his milestone, he started with his oft-repeated phrase: "I am not getting into that." However, the 69-year-old did allow himself the briefest of reflections on a career that has brought him glory way beyond what anyone could have imagined when he succeeded Ron Atkinson on November 6, 1986. "It is a bit of a fairytale to last so long," he said. "It has been a fantastic spell for me. It is something you don't think is going to happen and I appreciate that." Over the past couple of weeks, huge numbers of scribes have attempted to select Ferguson's Greatest XI. The task is virtually impossible given the huge number of star players who have been through United's doors since Ferguson began the quest to "knock Liverpool off their perch", something he finally achieved last May. Even on Thursday as he reeled off, just seven, those missing came instantly to mind. "When I look back I say to myself how fortunate I am to have had these players," he said. "The list is incredible, going back to the very start with Bryan Robson, Norman Whiteside, Brian McClair, (Mark) Hughes, (Paul) Ince, (Roy) Keane, (Eric) Cantona. What a collection of players. They were fantastic players. "It is hard to think I controlled all these players for so long. Now to the present era of players we see today, different personalities and different cultures." Inevitably followed the question no-one knows the answer to, least of all Ferguson. How long can he go on? "I will continue as long as I feel healthy enough to do it." There is no single secret to Ferguson's success. He is fortunate to have been at United just at the time when commercial aspects of football were starting to flourish. He also benefited from a patient board of directors, who could easily have dismissed him after three seasons without a trophy right at the start of his tenure. Other aspects of his management are entirely of his own making though. He was responsible for bringing through so many star players. Ferguson nurtured a succession of title-winning teams just when it seemed the search for glory was about to reach a dead end. And the relentless hunger and desire that keeps him going even now came from his own upbringing on the working class streets of Govan, and by nature the willingness to embrace vast change. "It is difficult to put everything in a box," he said. "I don't think you can do that. It is such a varied time in management. Things change as the years go on. There is a different way of managing today there was even seven or eight years ago."