Marcus Trescothick used to have a dream. It is the sort beloved of cricket-obsessed children, or desk-confined adults who imagine alternative lives as international cricketers. "I always dreamed," he says, "of the Oval finish where you raised your bat aloft and say, 'Thanks, that's my career done.'"

Ten years ago, on September 5, 2006, Trescothick came out to open the innings at the Rose Bowl in a humdrum, late-season one-day international of the sort that has become an English speciality. He was yorked by Shoaib Akhtar first ball. He pulled out of the last two ODIs of the summer, and then the Champions Trophy in India, citing a stress-related illness. That November he broke down in the dressing room at the Sydney Cricket Ground, and left the Ashes tour nine days before the opening Test. It was the second tour he had left prematurely in a year.

The Oval dream was not to be. He had played the last of his 202 games for England at the age of 30.

Over the previous six years Trescothick had made himself one of England's most cherished cricketers. This was not merely a reflection of his counterpunching batting but also the sense of normality and decency that he brought with him. As 21st-century international cricketers go, he was a little on the rotund side - called the "King of Junk Food" as a boy, he then became "Banger", after his penchant for sausage and mash. He would uncomplainingly do whatever the team needed, even serving as auxiliary wicketkeeper for five ODIs in 2002.

"Very often at the back end of tours I'd sit down and go, 'Do you know what, I can't continue to do all this.' I sort of bullshitted my way through it"

On the night of England's 2005 Ashes triumph, Trescothick and Ashley Giles eschewed an all-night bender and instead waited to receive the first editions of the morning newspapers.

There was always a hint of the West Country lumberjack to Trescothick's batting, defined by hefty forearms, scythes through the off side and a stubborn reticence to move his feet. But his runs underpinned England's progress to their 2005 summit: his 219 at The Oval against South Africa in 2003 secured a series draw; he waltzed down the pitch with impunity to drive Glenn McGrath for four fours in five balls in the semi-final of the 2004 Champions Trophy; another epic against South Africa, 180 in Johannesburg, ensured England won a series there for the first time in 40 years. Now all that was left was the Ashes itself: a blistering 90 at Edgbaston reinvigorated England in 2005 after an opening defeat that indicated a series straight from the 1990s playbook.

Yet this veneer of uncomplicated batting concealed the turmoil that lurked within. "Very often at the back end of tours I'd sit down and go, 'Do you know what, I can't continue to do all this.' I sort of bullshitted my way through it, and just tried to cover it up as much as I could do, without telling people what was actually going on - mainly because I didn't really understand it, and didn't know myself what I was going through."

There were signs early in his international career. He found a tour to New Zealand in 2002 onerous, exacerbated perhaps by taking on the new challenge of wicketkeeping. Initially when his spirit flagged on tour he thought it nothing more than homesickness. After becoming a father, in 2005, touring became harder. When Michael Vaughan was injured in Pakistan in late 2005, Trescothick dithered before accepting the captaincy. He then almost flew home after his father-in-law fell from a ladder and was in critical condition.

Edgbaston 2005: Trescothick's 90 got the classic Test off to a flying start Hamish Blair / © Getty Images

At the start of 2006, England toured India. A few days before they set off, Trescothick approached Steve Bull, England's sports psychologist. "I said to him," Trescothick remembers, "'Something's not right. I don't want to train, I don't want to practise, I don't really want to go away next week. I've got no interest in what's going on at the moment.'" His wife was suffering from post-natal depression, and he felt guilty going on with a cricket tour as normal.

But Trescothick did as he always had done: he carried on. This time it was too much. When Vaughan failed a fitness test, Trescothick was required to captain in a tour match, in Vadodara. He was in no state to do so, suffering panic attacks when he returned to his hotel room each night. "At that point I was a shell," he later wrote in his autobiography. "You could have taken all my kit, all my money, taken my life away. I didn't care." In the dressing room after the match, he broke down and was sent home. The team management was unsure how to break the news, leading to mixed messages: Duncan Fletcher said it was down to "family reasons"; Trescothick said that he had "picked up a bug".

When he returned to England, a doctor told Trescothick: "You've got depression". A few months later, in his first innings back for England, he scored 106 against Sri Lanka. But international cricket, which he had once relished, was increasingly a burden: not the game itself but everything else that went with it.

"When you're in the wrong frame of mind and you're not thinking rationally, playing in front of that crowd with the spotlight on you, it's bloody horrible." Following his return from the Ashes tour at the end of the year, Trescothick had to grapple with how to piece his life back together. He even considered giving up the game altogether.

Trescothick is motivated not by anger at the missed years with England, nor frustration at the riches and adulation he could have earned as a T20 specialist, but instead by a visceral relish for batting

"It's one of those things that always sits within you, that you're out of control in your brain. You invent things in your brain that make things a lot worse. What if this happens or what if that happens? And, of course, one of those things is, 'What if I can't carry on playing?' But when your brain becomes a bit more rational, and you understand it a bit more, and you're a bit more healthier again, then you sort of become normal-thinking in that aspect, and appreciate that's not going to happen. It's just when you're in a dark place at times, of course those sort of questions come to you."

Before the 2007 season, Trescothick returned to Somerset, and immediately sensed that he could still find fulfilment in the shires. "Once I got the whites back on, and all the kit back on, and then you go back out and continue playing - the minute you get success is the minute you realise, 'Yeah, do you know what? I was silly to think those type of things because it was not me - that was the illness.'"

County cricket is a different world from that which Trescothick occupied for his six exalted years with England. Taunton embodies county cricket at its most idyllic. This sleepy, low-key town has the county ground at its heart. It is famed for exquisite blackberry ice cream, a special section of the ground for owners to watch with their dogs, and a pitch that is among the truest in the land.

It was just what Trescothick needed. "I think it's easier at your home ground, isn't it? Your family's not far away." He grew up in Keynsham, a small town 45 miles away, and lives a five-minute drive away from Taunton.

Glove and affection: Trescothick willingly served as England keeper in New Zealand in 2002 Tom Shaw / © Getty Images

"There's less scrutiny involved, and the whole thing is just down a notch in the pressure stakes, so you're able to get back and enjoy it for what it is rather than getting stressed out about the other things that come along, which naturally you do when you're under in the pressure cooker of international cricket. These little things are there all the time, but they're not as great when you're playing down a level."

Not that Trescothick has ever treated county cricket like it is down a level. Returning to the county grind can hold little appeal to those who feel they have achieved all they want from the game. Nasser Hussain and Andrew Strauss did not play a single county game after they had retired from England duty. Vaughan, who is a year older than Trescothick, retired seven years ago, as soon as he realised that his chances of an England recall had gone.

For Trescothick and Mark Ramprakash, the two most sought-after wickets in the Championship over the last decade, it was different. For contrasting reasons - Ramprakash after he was dropped by England for the tenth and final time, Trescothick after his stress-related illness - the two returned to the shires with plenty more to give. Three years ago the writer Jon Hotten interviewed Ramprakash expecting to find "a brooding Heathcliff, banished to the deserted moors". Instead he realised that it was better viewed as "an act of love" for batting and for cricket. Much the same is true of Trescothick. He is motivated not by anger at the missed years with England, nor frustration at the lost riches and global adulation he could have earned as a gallivanting T20 specialist, but instead by a visceral relish for batting, especially at the club he has represented for 23 years.

"It's the love, it's the passion of the game, the excitement of what it gives you," he says. When he was appointed Somerset captain in 2010, a role he held for six seasons, Trescothick longed to be a history-maker and to lead the county to their first ever Championship crown. He hurled everything of himself into this quest. It was not enough. In 2010, Somerset finished level on points with Nottinghamshire but missed out on the title because they had won one fewer game - all they had needed to triumph was for Lancashire to survive 16 overs against Notts without losing three wickets. Between 2010 and 2012, Somerset were runners-up in six of the nine county competitions. In the T20 final in 2010, they muffed a run-out chance when Hampshire needed a single off the final ball to level the scores and win the title. "That still haunts me to this day," Trescothick says. "You wake some nights and think, 'Throw the ball!' or 'Someone run him out!'"

"You kind of get a grip of it, of course you do. But depression is a funny thing. When you're somebody who suffers with it, you've always got to be guarded"

Trescothick's enduring excellence in county cricket led to a clamour for him to be picked for the final Ashes Test in 2009. It was a notion he fleetingly entertained - until rumours of a recall led him to wake up in a cold sweat. He sent a text to Giles, who was an England selector: "Mate, I'm not interested. If you were thinking about it, don't bother. I'm done."

Trescothick is now the oldest first-class player on the circuit. His opening partner, Tom Abell, was not yet born when he made his first-class debut. To see him in full flow, you have to look closely to find the only discernible change from the batsman who thrived in international cricket 15 years ago: the spectacles he took to wearing a year ago. "The rest? No, nothing's really changed."

In the decade since his last England appearance, no one has scored more County Championship runs than Trescothick. He has passed 18,000 first-class runs for Somerset: second only to Harold Gimblett, who had himself suffered mental health problems in silence and committed suicide at the age of 63.

But all these imposing numbers are not the measure of his impact at Somerset. That is best measured in the mutual warmth between player and club. At Taunton they see in Trescothick someone they nurtured from stocky adolescence, when coaches used to force him to bat in four sweaters in the nets to sweat out the junk food. Always Trescothick relished coming back to Taunton when international commitments allowed, his essence unchanged by stardom. He has revelled in the chance to commit himself to Somerset.

Hotel illness: living out of a suitcase, away from home, increasingly was a source of stress for Trescothick Tom Shaw / © Getty Images

"The club has not just been a job for me and a career," he says. "It's been my home away from home for all these years. That's what it's been."

All the while, Trescothick has continued to confront mental-health problems. Until March 2008, he had hoped he would be able to return to the England team. But setting off on a pre-season tour to Dubai, he broke down at Heathrow and realised that he could not go abroad. A few days later he formally retired from international cricket.

Later that year Trescothick wrote his memoir, Coming Back to Me, which detailed his challenges in brutal detail. "Once I could manage to understand it myself, and knew what I was dealing with, we wrote the book, we told people, and the more I told people, the better it became."

Ever since, he has been far more open about his problems. "My reason for not talking about it in the first place was partly I didn't understand it. And you're always guarded about what the media are going to say. The less I've got to hide the easier it is for me. The light at the end of the tunnel was basically being honest and open and telling people about it, because as soon as I did, the reception was far different to that we all expected it to be - really the turning point for my life from that point on.

His impact at Somerset is best measured in the mutual warmth between player and club. They see in Trescothick someone they nurtured from stocky adolescence, when coaches used to force him to bat in four sweaters in the nets to sweat out the junk food

"You kind of get a grip of it, of course you do. But depression is a funny thing. When you're somebody who suffers with it and it's always lingering, you've always got to be guarded, because you don't know when you're going to suffer another bout of it. Each one is as bad as the next one. When you get it badly it knocks you back for a few weeks. I'm somebody who, if you get it badly, you'll be suffering for a good month, or where you strip everything back to basics. Touch wood, those are fewer nowadays, but it's always something you're careful not to try and take yourself back to, this dark place when it hits you all the time."

His coping strategies are "as long as my arm", taking in everything from what to eat to how to sleep better and how to keep himself busy. "I never was somebody who could ever really sit down to dwell on things that were happening," he says. "It was a case of, right, get up, get busy, do the things you've got to do, get your work done, and try and distract yourself from how crap you feel, you know."

His depression "almost lies dormant now, and just sort of flares up now and again. I don't think it's anything that will just naturally go away or disappear. I think it will just be lying there in the background for things to kick off." He still takes antidepressants every day.

In October 2009, Trescothick travelled to India with Somerset for the Champions League, but his illness forced him to leave after two matches. In the last two years Somerset have been on pre-season trips to Desert Springs in Spain, and Trescothick has been among the happy tourists.

Captaining England in Vadodara, 2006: "You could have taken all my kit, all my money, taken my life away. I didn't care" Tom Shaw / © Getty Images

"I've loved every minute of it, because it reminded me of what I loved about touring: you had that feeling of just pure relaxation at times, and being with the lads, which you do enjoy as a sportsman." It was a significant staging post in his recovery.

"I'm not ready to just suddenly jump on a plane and go off working around the world, but I know I that I can do it a little bit more."

Of all the innings he has played in a storied career, Trescothick reserves particular pride for a game at Headingley in early 2010. On the face of it this seems curious: in Trescothick's first match as full-time captain, Somerset were defeated.

The significance lies in how he overcame himself. He arrived at the ground in a wretched state and considering pulling out of the game. "I felt awful. Going into the match, I thought, 'I can't be captain, I can't cope with the pressure of it already' - and this was the first game of the season." His condition was so obvious to his team-mates that they feared he might even retire his innings; Somerset's chief executive Richard Gould moved to the media centre ready to explain if he did.

"There's letters you get saying, 'You saved my wife's life.' That's incredible to hear. You know you've done something good"

"I felt so bad and I thought I was going to break down at any minute when I was out in the middle, but I forced myself to stay out there and I concentrated my ass off," Trescothick recalls. He ended up scoring 117. "I was like, 'That's great. If you can perform under that amount of pressure, then you can do anything.'"

It embodied his approach of dealing with the illness. "There's probably times when I could have taken a day off or taken a game off and said, 'I'm not well enough', but I never have done that because one of my biggest things was to carry on my daily life and just be busy and play the game. There's probably been many a game where I've not been up to scratch and been a 100% focused on what I've got to do."

Though runs on a cricket ground are insignificant against Trescothick's challenges, they have a cathartic effect. "The biggest healer when you're in that sort of environment is when you succeed out in the middle, because you get the buzz of scoring runs," he says. And the captaincy, which he held for six years until 2016, was a help. "When you're feeling rough and you think you're in a dark place, you focus internally on yourself, but when you're captain you can't do that."

Over this journey Trescothick has done much more than learn to manage his problems: his openness, the copious hours he has devoted to raising awareness about mental-health issues, have helped hundreds of others manage theirs. "There's letters you get, saying, 'You saved my wife's life.' That's incredible to hear. You know you've done something good. There would be so many emails, letters, postcards we've had along the way, which has been fantastic."

He hopes other cricketers will learn from his "mistake" in not confronting his problems for so long. The spate of players who have followed him in speaking up about their challenges with mental health include Andrew Flintoff, Steven Davies, Michael Yardy, Jonathan Trott, Sarah Taylor and John Mooney. The catalogue of suicides among ex-cricketers, documented in David Frith's Silence of the Heart, invites the question of whether there is something about cricket that makes those who play it particularly susceptible to mental-health problems, or whether the game attracts those who are vulnerable to them. Trescothick "can't see how we could be any different or more susceptible being professional sportsmen than any other person walking down the street". The most recent Professional Cricketers' Association survey of past players, in 2012, suggested that one in five had struggled with anxiety and depression, which is actually slightly below the national average of one in four.

The elder statesman: Trescothick, seen here with Lewis Gregory, is one of the oldest players on the county circuit Dan Mullan / © Getty Images

Trescothick believes his problems would have been picked up earlier in today's climate, though he has "no idea" whether this could have prolonged his own international career. Besides, his interest now is more in preventing other people from going through a similar ordeal. "It could still be better. And the more we talk about it and be honest about it and open up, then the more people who don't suffer will understand, and can relate to it."

On July 5, 2016, Mohammad Amir and Pakistan had 73 overs to bowl out Somerset in the tour opener: more than twice the time they needed in the first innings. They did not manage it, largely because of Trescothick bunting the ball through the off side, uppercutting impudently, harrumphing a slog sweep over midwicket for six. The upshot was the 61st first-class century of his career and the 47th for Somerset, taking him level with Viv Richards. He has since scored another two, drawing him level with the record holder, Gimblett.

It was tempting to think of all those lost runs for England over the last decade. Despite playing in only one World Cup, he had set an England ODI record for most centuries, which remains unbroken. He was on course to be England's first player to 10,000 Test runs, and would have been a terrific T20I player too. Yet rather than embitterment there is gratitude for what cricket has brought him - 26 international centuries, a crucial role in the 2005 Ashes, and partly because of the premature end to his international career, a treasured status at his county, unmatched by his England contemporaries. Cricket has given him so much: "The runs, the friendship, the wins, everything."

At the age of 40, bespectacled and a little slower than he once was, Trescothick is still pounding balls through the Taunton outfield. Since 2008, supporters have been able to watch him do so from their seats in the Marcus Trescothick Stand. Giving up limited-overs cricket has allowed Trescothick to watch matches there with his children.

"To watch the cricket from a stand that has your name on is a bit odd," he says. "It's something that I wanted to do - just to go and have a look and see what it all looked like from that angle. But it is quite nice. It's just a little extra perk that has come along through my time of playing."

Tim Wigmore is a freelance journalist and author of Second XI: Cricket in its Outposts

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