Scott Boswell is sitting in the school canteen at Trent College in Nottingham, tucking into his lunch. The kids he teaches are swarming around him. But his mind isn't quite here. It's turning back to 1 September 2001. The C&G Trophy final at Lord's. He thinks about it a lot, but hasn't discussed it much in public. This is the first newspaper interview he has given since. He told plenty of journalists to "eff off", because, he says, "it literally took me 10 years to get back from it".

What if you got your shot and you blew it? What if you had the chance to realise a dream you had harboured since childhood and it went horribly wrong?

Boswell was 26, seven years into his career. He had settled at Leicestershire, where he was enjoying one of his best seasons yet. He had become a regular in their one-day side. They were on a good run, too, winning 11 out of 13 in the old Sunday league, easing through the rounds of the C&G Trophy. In the semi-final, a home tie against Lancashire, Boswell took four for 44, all of them England players. They were the best figures of his career. And they took his team to the final, where they would play Somerset. "It was," he says, "going to be one of the best days of my life."

Most cricket fans will remember what happened. Many of the rest may know about it from YouTube, where, as Boswell says with wry pride, he "has had well over a million hits", plenty of them from the children he now coaches. The video is called "The Worst Over Ever?" Six of his first eight balls are wides. There were, at one point, five in a row. The bemused batsman, Marcus Trescothick, hits a couple of the straighter balls for four. It lasted 14 balls and it ended Boswell's first-class career.

"I had heard about people getting the yips gradually," Boswell says. "But I got the yips because of an occasion. I choked." It has taken him a long time to be able to use that word. He can laugh about it now, just about. "It's OK when the jokes are on my terms, but when somebody comes to me and talks about it, even a little kid, I find it a little bit raw." If the pupil is old enough, he will explain that what happened that day cost him his job. What he doesn't say, has only recently admitted to himself, is that the trauma of it has shaped his life since.

It began the night before the final. Boswell hadn't been at his best in the weeks since the semi. He knew it and so did everyone else. The coaches were in two minds about whether to pick him and told him as much. In a meeting that night a senior figure at the club told Boswell "not to fuck up". That stuck in his head. Finally, late the next morning, they told him he had been selected. "And I thought: 'Bloody hell.'"

He was, he says, "a nervous cricketer". His action, he admits, "wasn't a biomechanical dream". But the first over was fine. "Peter Bowler cut me for four. But I felt OK." When he came back for his second, Trescothick was on strike. Boswell's head started to swim. He had been struggling to bowl to left-handers. Suddenly Trescothick "looked as though he was 50 yards away. He was like a tiny dot. I just couldn't see him. Then I bowled a wide and I heard the noise of the crowd. I bowled a second wide, and the noise got louder and louder and louder." His muscles grew tight. His fingers grew tense. He began to sweat. "I just couldn't let go of the ball. I wanted to get on with it, so I began to rush. The more I panicked, the more I rushed." He lost his run-up. The pitch, already on a slope, seemed to tilt sharper beneath his feet. He makes it sound like vertigo.

No one spoke to him. He didn't want to talk anyway. He just wanted to get it over with. The umpire, George Sharp, finally said, out of the side of his mouth, "keep bowling". Boswell thought: "Jesus Christ. I am going to be bowling here all bloody day." He was terrified that the over would never end. "'I was thinking: 'I just want to get this over, I just want to get this over' but it kept going and going and going, wide after wide after wide." Some flew to slip, others flew towards fine leg. The video is harrowing.

Finally it was over. 2-0-23-0. Boswell went down to fine leg. The ball came his way. "I can dive for this." He did. And he missed it. Worse, he tore up a lump of the Lord's turf. "It landed on my head. So I was lying on the floor and I look up and there are 2,000 people behind me, and I see the ball trickling over the boundary. I have this bleeding lump of turf on my head. I thought: 'Fucking hell. This can't get any worse. Get me off this field.'" He froze. Literally. "There was a water bottle five metres away from me. My mouth was so dry. But I couldn't move. I couldn't walk five metres to go and get it." The Somerset fans chanted "Bring on the Boswell! Bring on the Boswell!" That, he says, "haunted me for a couple of years".

Leicestershire lost. "We were playing Gloucestershire on the Monday after the final. Nobody spoke to me, I just wasn't playing, that was it. I wasn't told." Only one close friend, the former England bowler Jimmy Ormond, tried to talk to him. "People would just walk past me. But Jimmy took me out for a pint and he just said: 'What the hell happened there?' He was the only person who confronted me, the only person who I talked to about it. But all I could say was: 'Yeah, what did happen there?'" Leicestershire tried to send him to a sports psychologist, but he just wasn't ready to talk about it. Then the emails started to come. Hundreds of them. Some sympathetic, some ugly, the worst accusing him of match-fixing.

Two weeks later, Leicestershire sacked him. Then they asked if he would play one last match, against Nottinghamshire in the Sunday league. They needed to win to secure the title. He wasn't thinking straight. So he said yes. Just before the game began he was hiding, crying, in a shop near the ground. "I was absolutely terrified." He came on first change and bowled a wide. "I heard a couple of people cheer and that was it." The over cost 18 runs. So he feigned cramp and ran off the field. He spent five hours sitting in the changing room, stunned. There had barely been a day in the past 10 years when he hadn't bowled a cricket ball, up and down, one end to the other, and now he just couldn't do it. "And that was it. I disappeared."

A week later Boswell started life in what he calls "the real world", as a salesman for a cricket company. On his first day he spent five hours in a traffic jam on the M6 thinking: "Oh my God." He wanted to carry on playing. A couple of clubs offered him deals, decent money. He went up to Preston and bowled fine in the nets. But in a match "I couldn't let go of it. It was going from my hand to the keeper, to third slip, I had no idea. I felt sick. I would actually be sick. I was throwing up all over the place. I couldn't do what I had been doing for so long."

Different men have dealt with the yips in different ways. Some resign themselves to it, quit bowling, or even cricket. Boswell couldn't let the game go, didn't want to, but the disorder got to him. "I dwelled on it for a long period of time." He began to get depressed. "I put on a lot of weight and I was drinking a lot. I didn't socialise, I lost a lot of friends. But I didn't do anything about it, because I thought: 'I'm a man and men don't do those things.'" He had a heart operation in 2006. He woke up one morning in hospital and thought: "I can't go on living like this." That was the first turning point.

The second was at a barbecue, when a friend told him he should take a place on a training programme for new teachers being run in a local state school. The third was when his wife, "my rock", went to a life-coaching course, and, as a couple, they learned about the power of positive thinking. Boswell was still playing. And he still couldn't bowl. He was a batsman for a club side in Leicestershire. "There was a guy there called David Pounds, a club cricketer. We were playing a second XI match and he forced me to bowl. I bowled a 28-ball over. The opposition were OK, because he had told them about me. But I hated it. The ball was going everywhere." And then, it happened. "My 28th ball, I landed it. I got an lbw. Everybody ran up to me and I was on the floor in tears. I was the most embarrassed man in the world, but I had a wicket.

"After that, I gradually began to get back to bowling." Now, at the age of 38, Boswell can put the ball wherever he wants. "But it is always there in the back of my head, when I'm bowling it will pop into my head: 'I could bowl a wide, I could bowl a wide.'" Just hearing the phrase "leg side wide" still causes fluttering thoughts of panic. In 2009 he was playing for Kibworth Second XI when they got to a Lord's final. Boswell was 12th man. And of course someone got injured. "I had to go on the field. Bloody hell, I was holding back some tears." But it felt good. Like he had confronted his demons.

Boswell says he thinks too much. He has spent a lot of time trying to understand what happened and why. He had to turn off the TV during the fifth Ashes Test when Simon Kerrigan was bowling. He doesn't doubt that Kerrigan "yipped up". He knew exactly what he was going through. "The occasion got to him and he couldn't let go of the ball. I found it too hard to watch. I would like to speak to him and it would be interesting to know how the coaches have spoken to him. It is a mental thing, not a technical thing. The one thing he has to do is get back bowling again, quickly. You have to get back on the horse."

Like a man who has acquired his medical knowledge from reading up on his own disease, Boswell has become an excellent coach, enthusiastic and knowledgeable. Trent College play up to 12 matches each Saturday, with as many as three teams in each year. They even run umpiring and scoring courses. He has learned to love the game and its simple pleasures all over again. He has been doing his ECB level four coaching course at Loughborough, along with Graham Thorpe and Jimmy Adams. "I never used to think much when I was a player, but now I'm always reading about coaching, always learning about it." He went to see England play Pakistan, just to watch the warm-up drills. "It's so sad, but I find that the most interesting bit."

Boswell doesn't say it, maybe doesn't even realise it, but his approach to coaching has obviously grown out of his own experiences. He is happy to show his vulnerable side to his students and he is extremely careful with his words, always mindful that a few poorly chosen ones ("don't fuck up") can scar. He tries to make sure that there are consequences for everything the teams do in training – they don't get kit unless all 11 of them average a certain score, as a team, on his fitness tests – so they are ready for the pressure when it comes. And – a glorious twist this – he has even invented a bowling mat which lights up when you hit a good length, which he is hoping to release commercially.

"Sometimes," Boswell says, "I wonder if I hadn't played that match, would I still be playing cricket professionally? But then I tell myself that this happened for a reason." This year, for the first time in a long time, he didn't play a game of cricket. "I had put it to bed. I could bowl. I could bat. I had never been happier."

• This is an extract taken from the Spin, the Guardian's weekly take on the world of cricket. Sign up for your free copy here.