People will tell you that when someone of power and prominence walks into a room, before you have even seen them, you feel their presence. It’s an absurd notion really. The idea that anyone has an invisible aura of authority or influence is at best descriptive indulgence, more accurately it’s physically not possible. But the first time I stood in the small press conference room at Manchester United’s Carrington training ground as a fresh-faced 21-year-old reporter (no joke, I looked about six at the time) and Sir Alex Ferguson walked into the room, I knew he was there even before I heard the brisk Govan brogue of his businesslike “Morning”. Was it an aura? Or just respect from everyone in the room – reverence, and fear? Either way, I’ve never experienced anyone else have quite the same effect. Journalists were like schoolkids: “he’s coming,” before sitting neatly in their seats, while the timing of placing dictaphones on the top table was hilarious to observe, judged astutely for another ‘good morning’ and maybe some idle chit-chat, or done stealthily if something critical or negative had appeared in their paper.

I don’t say that to disparage other journalists, far from it. It was just a sign of Ferguson’s all-consuming influence, and reporter’s respect for him – at least to his face.

In nine years working in Manchester United’s media department – and you’re not afforded quite the intimate access some fans expect – I never lost the nervous feeling, the butterflies in the pit of my stomach, before interviewing Ferguson one-on-one, which these days is a rare privilege for any journalist. The first knock on the door to his office, which overlooks the vast green of scattered football pitches at United’s hideaway headquarters (like the all-seeing eye of Sauron), felt like it took courage in itself. You may laugh at that, but I guarantee you would be the same. I’ve seen grown men crumble in his presence, reduced to gibbering wrecks under that murderous blue-eyed stare.

In that first trip to a Friday press conference, a trip I rarely liked to miss, I was stood in the now-defunct huddle of radio reporters. I’d not been introduced to the boss at that point. He made a joke and I laughed along with everyone else, but then he stopped smiling, turned to me and said sternly, “where’re you from, son?” Ridiculously nervous, I struggled to muster: “The club website.” “Ok, son.” I think it was an ‘I’m in control here’ warning for a new face. And whenever you spoke to him in an interview it was sort of like that. I sometimes thought that it didn’t much matter how good your questioning was, how clever or cute you were with the wording, you were only going to get the answer he wanted to give you. Not one word seemed misjudged, unintended or squandered. That’s a key trait. He is acutely aware of the influence of his actions and words, often used perfectly for effect.

There will be plenty written about his on-field success during the week of his 25th anniversary as Manchester United boss, but almost as remarkable are his performances off it. He’s a first-class orator, a PR guru, a psychological mastermind and a great actor. The week in which Wayne Rooney’s loyalty wavered was just about everything that I admire and about Ferguson. His performance was enough to change Rooney’s mind, reiterate his own status as top dog, but more than that it was a spine-tingling performance of his belief in what he and Manchester United stand for. It was incredible stuff.

As well as never losing my pre-interview nerves (I was never like that with players), I also never lost the jubilance after an interview with the boss, hopefully with some typical Fergie lines in the bag. After interviews, the good lines run through your mind like a post-match analysis of how well the interview went. The best thing was being given even brief access to an encyclopedic mind; not just on football, but other sports, history, film, politics, Scottishness, just about any subject could inspire an interesting response. His memory is astonishing, too. I forget matches I’ve worked at and written about in the same season. Ferguson would remember his school caretaker’s cat’s name from 60 years ago, an opposition left-winger from his days at Aberdeen, or a defender he skipped past to score a goal for Rangers – and he could talk for hours about goals he scored.

I’d never overstate the position I held, but I feel privileged to have worked in even mildly close proximity to one of football’s greats. I’m well aware I could be accused of sycophancy, blind faith, arse kissing. There’ll be a lot of it about as Ferguson reaches this milestone, and plenty of seething curses from City and Liverpool fans too, no doubt.

For all my own personal praise, for the little it is worth, I certainly wouldn’t describe Ferguson as a Saint. He can be ruthless, unyielding, bullish, pugnacious and controlling, as any critic will tell you. But they are the fiery characteristics that fuel his ferocious drive to succeed. It’s part of the package.

Then again, there’s a softer side that rarely gets seen too; the many personal letters he writes each week to help or advise people, many just ordinary fans, the functions or funerals he attends, the loyalty and respect he has for long-serving staff, for former players who’ve hit hard times. You occasionally get a glimpse of his humour, a razor-sharp wit. With no cameras or microphones in attendance he is rarely without a smile. You can tell he has lived his life in football; he’s often involved in banter with coaches and staff in the Carrington canteen. He’s loud, too. Christ, his voice carries. A colleague was interviewing him on the balcony at Carrington’s reception and he heard Darren Fletcher, then a young reserve, walking through the doors downstairs. He stopped mid-answer and bawled: “FLETCHER! FLETCHERRRR!” as though he were warning a young child crossing a street into oncoming traffic. It nearly burst the speakers. Perhaps Fletcher knew what it was his manager was so keen to talk to him about, because he promptly walked on. Perhaps he ran. Ferguson sings as well, mainly crooner classics, like Sinatra, and usually after he has finished his media duties on a Friday morning, of which you can tell he has grown tired. After 25 years I think he has become weary of the inquisition. Allowing journalists in a free media to ask questions, favorable or not, is absolutely still vital, but Ferguson increasingly uses his programme notes to communicate his undiluted message to fans, and the world.

It’s said that no one is bigger than the club. When it comes to players, that’s true. But what about when someone’s philosophy and direction defines the club in the modern age? Nothing of importance that happens at Manchester United goes without Ferguson’s knowledge or approval. He is as close to impossible to replace as any manager could be. Good luck following this act.

Personally, I think he is far from done yet. I can’t even picture the day when he will walk away. He has said that if you don’t keep the mind active at his age, it’s a downward spiral from there. That’s a solemn thought. But it shows what Manchester United means to him that he is sticking around into his 70s: it’s his life. And United fans should be thankful of that as this milestone clicks round, privileged to have enjoyed his quarter of a century at Old Trafford which has provided more success and unforgettable moments than any manager, even a brilliant one, has any right to expect. Maybe it’s that success that gives him presence, the aura people speak of. Whatever it is, he is a unique, incredible man and, moreover, the best manager British football has ever seen – for me, to borrow one of his phrases, there’s no question about that.

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