"I'm in a tunnel that has no end, and no light. There is no point continuing to struggle against the odds ... the psychiatrists don't know what is wrong with me, and there is nothing they can do in any case... If I was on a life machine I suppose one could switch off. I don't want to see anyone. I've nothing to live for. There's no point going on."

Soon after he said that, Harold Gimblett took an overdose and died. Those words are a succinct summation of the distressed, depressed state of mind he was in before he killed himself. Tragically, the first time they were heard by any ears other than his own was after he had died. They were set down in weary and broken monologue on a series of rambling tape recordings which he made for David Foot. The two had been planning to write Gimblett's biography together. It never happened, but after Gimblett's death Foot took the material he was left with and wove it into one of the touching books about the game and the people who play it, Harold Gimblett: Tormented Genius of Cricket.

Depression was always with Gimblett. He called it "the black cloud" and it followed him as closely as his own shadow on a sunny day at the wicket. He was convinced it was his inheritance from his father, who worked the farm at Bicknoller from where his boy hitchhiked to Frome to make one of the most rambunctious and glorious debuts in history. By 1953, 18 years later, Gimblett couldn't take it anymore. "I was taking sleeping pills to help me sleep and others to wake me up. The world was closing in on me and I couldn't offer any reason why." He was admitted to Tone Vale hospital and given a course of electric shock therapy.

Gimblett came back to cricket too soon. In his next match "I just folded up and had to stop the game while batting." The middle had been his sanctuary, once, but now he only felt secure in Tone Vale. "I'd felt so safe there. No one could get me." He struggled to make 29 and then "back in the dressing room I was at the bottom of the pit ..." In his next first-class innings, the last of the 673 he played, he made a duck, walked out of the County Ground at Taunton and checked himself back into hospital. The club's committee never forgave, or forgot, this desertion, and the ensuing rancour still riled him when he took his own life, aged 63, 24 years later. One of too many suicides: William Scotton, Arthur Shrewsbury, Albert Trott, AE Stoddart, Aubrey Faulkner, RC Robertson-Glasgow, Jack Iverson, Sid Barnes, David Bairstow and Mark Saxelby.

In my mind and those, I imagine, of a few other Somerset fans, Gimblett still opens the batting at Taunton. Or at least he does in the early hours of the night, when I'm caught sleepless between the sun's set and rise. Compiling XIs is like counting sheep to me. He and Marcus Trescothick are the openers in the county's All Time side. Strange, the similarities between the two, both ostensibly so uncomplicated, and yet each carrying a melancholic streak as broad as the opposing bowlers found their bats to be. Unlike Gimblett, Trescothick was bold enough, brave enough, or perhaps simply able enough, to talk about his own illness while he was still playing. "The mental battles for me have been enormous," Gimblett told Foot. "And maybe it would be a good idea to put it on record." Trescothick must have had a similar sort of conversation, in his way, with Peter Hayter, his own ghostwriter.

It has been four years since Coming Back to Me, the book the two wrote together, was published. It won the William Hill prize. But it's only now that the impact of it is really being felt and seen. There have been better books written about cricket, many more colourful, or more insightful, but not many that have been as important. Last week Steven Davies, the Surrey wicketkeeper, became the latest player to talk publicly about his own depression. In his case, it was triggered by the death of his team-mate Tom Maynard last June. "I really struggled," he told Surrey TV. "I knew I just needed some family time. I had a bit of break away and now I'm ready and really looking forward to the 2013 season." His form fell apart and he was rested, rather than dropped, from the Surrey side last summer.

Davies, it has to be said, was lucky enough to find an unorthodox but, he says, effective remedy. He took some time away from cricket, and went off on tour with Elton John. "Since I came out, we've bonded," Davies said. "He's looked after me in many ways, he knew I was going through a hard time and I mentioned that I was going to take some time away from cricket. He said that winters in England can be a bit depressing and he asked me 'Why don't you come on tour with me?' ... I had a great time."

Tim Ambrose, Mike Yardy and Iain O'Brien have all suffered too, and all spoken about it. The three of them have all contributed to a new awareness and advice program run by the Professional Cricketers' Association, Mind Matters. A book on the subject, with a foreword by Trescothick, has been issued to all PCA members this season. It's easy to forget now, but when Trescothick first flew home from England's tour to Pakistan in 2006, the official line was that he had "family problems", an explanation he then contradicted when he insisted that he had picked up a bug on tour. "In that old macho way," he later wrote, "I didn't want to admit to anyone what the problem might be." A lot had changed by the time Yardy left England's World Cup campaign, only five years later.

There's a temptation to cast cricketers as a species who are more prone to such problems than those in other walks of sport. "Like few other sports of the field," as Foot put it, "it is a game played with the mind. Only the unimaginative escape the tensions." Perhaps. But it would be a mistake to think that there is such a thing as a monopoly on misery. You wouldn't need long to find equally severe cases of depression in the ranks of players of other games. It is just that cricket has done a better job than most of casting light on the darkness, and is quicker and keener to address the issue. The fans and players, so easily and often teased as the one of the more conservative communities in sport, have been enlightened by Trescothick's confession.

Scorn has turned to sympathy which has turned to empathy, though it didn't happen in time to save Gimblett, or any number of others. His recordings, set down verbatim in Foot's book, remain the bleakest possible reminder of the depths sportsmen and women can sink to. You have to hope that, thanks in part to Trescothick, few will fall so low again, or be so lonely if they do.

"Maybe the coroner will listen to this and think what a load of rubbish it is. It is just a very unhappy, a very sad, a very disillusioned man saying out loud the thoughts that go round and round in his head. There is nothing I can do about it ... I'm a freak. Born one and always to be one ... There's a big weight pressing down on me. If I take tablets, it will be because I want to ..."

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