Six days ago, Scott MacLeod faced a fevered press pack to tell the world that he had violated anti- doping regulations. Chief rugby writer Alasdair Reid hears the inside story of a dramatic month for the lock

Someday he'll make sense of it all, resolve the headlong rush of events into something he can understand. Someday it will be a story with a beginning, a middle and an end, not a mind-addling whirl of places and paperwork, doctors and lawyers, stern-faced officials and the baleful glare of a battery of television lights. Someday it will all add up for Scott MacLeod.

But not yet. Thursday lunchtime in a dimly-lit upstairs room at Llanell's Stradey Park clubhouse, and the distinctive beetle-browed features of the towering lock forward are still furrowed by confusion. He is here to talk happy to talk of the circumstances that catapulted him from the back pages to the front, from anonymity to notoriety, from stalwart service in the Scotland second row to live-on-Sky exposure for failing a drugs test. But his bewilderment says more than anything.

After all, he didn't ask for asthma. He didn't ask for those times, as a child, when he was rushed to hospital fighting for breath, or when his extreme allergy to horses, a common trigger for attacks, meant he had to get out of Hawick at the height of the Common Riding season. He didn't ask to have a lifelong reliance on the bronchodilator inhalers that open up his airways and allow him to lead a normal life.

"There were a couple of times as a youngster when he was really ill," said his father David last week. "It makes me all the more proud to see what he has achieved despite his problems. He still can't go anywhere without his pockets bulging with puffers and hankies." And yet the same inhalers that have been his lifeline for the past 20 years could have stopped his career in its tracks 13 days ago when he stood before a three-man tribunal at Murrayfield flanked by Scotland team doctor James Robson and team manager Guy Richardson. Had they decided that he was solely responsible for what was in his system, and that the traces of Terbutaline in his urine could not be excused by ignorance or an administrative error, then he would not be preparing to play Ireland a few days later but bracing himself for a lengthy ban and the humiliation of being branded a drugs cheat.

The facts of the case are now well known. Terbutaline is the active ingredient of the Bricanyl inhaler he has used for many years. However, when he was granted a Therapeutic Use Exemption (TUE) he had temporarily been switched to Salbutamol, another drug from the same family, due to a supply shortage. Mistakenly, he believed his TUE applied to his asthma condition rather than the specific medication used for its treatment.

"That's the thing that's been so difficult to get my head around," he sighs.

"I'm the one with asthma, but because I hadn't stated one minor detail on my form that could have been my career gone. It's a short career anyway, so it's unthinkable to have it broken by something so minor. The embarrassment would have been hard to live with." The first sign that anything could be wrong had come in a phone call from SRU international administration manager Gregor Nicholson. It was Thursday, February 14, and MacLeod was at Edinburgh airport, waiting for his flight to Cardiff, when Nicholson rang his number.

"He was saying 'you've failed a drugs test'. I was just like 'sorry? That just can't be possible'. He said I had Terbutaline in my system and I said, well yeah, that's what I take. But it's not on your form, he said. Even then I didn't realise how big a deal it was. That didn't happen until I went to the tribunal, and I was hearing things like 'you could be banned for a year'. Big stuff, scary stuff." The tribunal was the following Monday. Strictly speaking, he was already banned from playing, but Llanelli had decided to rest him for that weekend's match with Glasgow so he had no need to tell anyone at the club what had happened. Nor did he tell any of his Scotland team-mates. "I told my wife and my parents and that was it," he says.

"Over that weekend before I went back up to Edinburgh, I had plenty time to think. But I still didn't feel like I had failed a drugs test, because this is something I've always taken. It's normal, it's not wrong. The thing I felt a bit stupid about was it not being on my form. I wasn't really worrying because I couldn't really see what I had done wrong.

"Once they'd met me, heard my side of the story and saw that it was just an admin mistake, I didn't see how anyone could find me guilty of anything.

It's not that I'm the victim, but I don't take my inhaler because I like to.

I take it because I have to take it. I expected to be rapped on the knuckles for the admin thing, but you can't go banning people for taking their inhalers."

MacLeod had to break off from a Scotland training session to attend his hearing. Even afterwards, with the match against Ireland just a few days away, he kept quiet about why he had gone. "The boys were all asking me about where I had been," he says. "I just muttered something about personal issues." The tribunal was held in one of Murrayfield's hospitality suites, high above the pitch in the north-west corner of the ground, at 3pm. MacLeod stated his case to the panel of Rod McKenzie, a lawyer, and medical experts Professor Donald Macleod and Dr Brian Walker. Having been grilled on the matter "the lawyer guy was quite intimidating" he was asked to leave the room. Half an hour later he was brought back in to be told the tribunal accepted his explanation and that he would receive only a warning and a reprimand.

He was, in effect, free to go. The following day, he was named in the Scotland starting lineup to face Ireland he had been among the replacements for the earlier matches against France and Wales and he could concentrate on his preparations for that. He had been told he could lodge an appeal within seven days, but there was nothing to be gained from doing so.

MacLeod is the essence of straightforward. When he talks to the media there is no spin, no circumlocution, no need to read between the lines. What you see is what you get: a big, honest bloke. "Scott couldn't tell a lie if he tried," said one former team-mate at Hawick.

"In making today's announcement, we were under no regulatory requirement to name Scott," said Nicholson when the case came to light last week. Perhaps it had not occurred to Nicholson that the SRU is actually something more than Scotland RFC, and that the governing body of a sport still has an overwhelming moral obligation to act with honesty and transparency.

Thankfully, the thought of sweeping the affair under the carpet never crossed the mind of MacLeod himself.

Astonishingly, however, the Union put out a teaser press release early last Monday morning. 'Scotland Player Anti-Doping Violation' was the heading, above a terse statement calling journalists to a press conference at Murrayfield barely an hour later. It was the media equivalent of an air-raid siren, resulting in camera crews, sportswriters and news reporters racing towards the Edinburgh stadium. To make matters worse, the hastily convened gathering was brought to a peremptory conclusion as soon as the questioning became a little awkward, and MacLeod was quickly ushered from the room.

He says: "It would have been nice to have a chat with the journalists afterwards as I have nothing to hide, but I was just whisked away. I got a real fright when I walked into that room and saw all the cameras. I thought 'this is all for me taking my puffer?' "When you look at it properly, it's quite a boring story, me taking my puffer and not having it on my TUE. I hadn't been that nervous up to that point, even preparing for the tribunal, because I felt they had to see reason; once they heard my side of the story, they would have to see that it was a simple and honest mistake. It wasn't performance-enhancing or anything. It has been a weird few weeks." Nor did the union cover itself in glory with the appointment of a tribunal of individuals with known connections to the governing body. MacLeod's innocence was more persuasively stated by UK Sport, who carried out the original test, and the International Rugby Board, the world governing body, who both expressed satisfaction with the conduct and outcome of the case.

Without their approval, the suspicion that self-interest had prevailed would linger around Murrayfield like a bad smell.

It was all the more important for the union to handle the case correctly as the media is not exactly short of sanctimonious hand-wringers whenever the subject of drugs in sport is aired. Their pious proclamations of zero tolerance may be nothing more than tacit admissions of zero thought, but it is a black-and-white world in which the gap between clean as a whistle and guilty as sin is dangerously slim. Justice must be seen to be done in a professional age in which the SRU has become the paymaster and profit centre of the sport, and where there is a heightened suspicion that its instincts are increasingly towards pragmatic self-interest rather than the wider moral welfare of the game.

It is perhaps just as well, then, that MacLeod is such an open book on the matter. The experience will have had a cautionary effect on him, but it is unlikely to erode his instinctive honesty. That quality was just as obvious as he looked ahead to next weekend's Calcutta Cup clash with England at Murrayfield and recalled Scotland's 18-12 win in the equivalent fixture two years ago. It was his first start for his country, but he had no qualms about admitting that he hadn't played particularly well.

So if the shoulder injury he collected in a clash with Brian O'Driscoll last weekend clears up, next Saturday will offer a chance of redemption in more than one sense. Of all the things that have been baffling him recently, Scotland's failure to click in their three Six Nations games this season is right up there with the machinations of the disciplinary process he has just gone through. "We're due a big performance," he says with quiet determination.

The past few weeks have shaken Scott MacLeod, but he has learnt a lesson.

With his wife Adele due to give birth to their first child in August, he has other things to look forward to, but his glimpse into the abyss of being banned from his sport has reminded him how lucky he is to live the life of a professional player. Someday, he knows it will all end. Someday but not just yet.