How much of a sportsman's story do you need to know?

I probably shouldn't admit this, but on Thursday, while researching a book I'm writing on Argentinian football (it's called Angels with Dirty Faces, and it will be out, well, when it's finished), I came upon a figure I'd never come across before, a man called Jim Lopes, who seems to have coached the Argentina national team briefly in 1962 and 1967. My initial reaction was to be appalled. I've spent much of the last six years shuttling between Buenos Aires and London, conducting dozens of interviews, reading dozens of books and watching dozens of DVDs, and yet I'd never heard of him. How could I have missed him?

So I did the natural thing: I looked him up on Wikipedia. It turns out he has no page in English or in Spanish, but he does have an entry in Portuguese. I'm still not entirely convinced he's not an elaborate internet hoax, but he appears to have been a journeyman coach who spent most of his working life in Brazil. One detail, though, even in the bald details of that Wiki entry, stands out: he was born Alejandro Galan, but was known as Jim Lopes. How does that work? My desperate but probably vain hope is that he or his family had to change his name to escape a crime syndicate or the law, that his peripatetic career is explained by the fact that he was on the run.

I mentioned the story to a friend, whose immediate response, as a sort of semi-joking criticism, was, "Oh, you want to know everything." And of course she's right: that's the job of the journalist or historian; that's kind of the whole point of the exercise. And yet the fan in me rebels against that. The loss of mystery is a terrible thing.

Take the case of Josimar. Barely anybody in Europe had heard of Brazil's reserve right-back before the 1986 World Cup when, thanks to an injury to Édson, the first choice, he suddenly emerged, a fully formed cult hero, belting in two ridiculous goals from miles out and bombing up and down the right flak with gleeful abandon. Kids across the world (well, across the playground of my primary school in Sunderland) started yelling his name when attempting long-range drives. His mystique endures to the extent that a Norwegian football magazine has been named after him. Yet part of his appeal was that he was an unknown. He came from nowhere and, in the end, won only 16 caps. Nowadays, with the blanket coverage of sport, we'd have known for weeks before the tournament that Édson was a doubt and we'd have tracked the progress of his probable replacement, this moustachioed 25-year-old from Botafogo.

It's not a comfortable position to be in. On the one hand, my job is to hunt down obscure players, analyse them and write up their stories - and I love doing that; on the other, I'm aware that by doing so I'm destroying part of what I most enjoy about sport. As a journalist, I want detail and nuance. As a fan, I'm lazy: I'm quite happy with archetypes, with basic narratives that follow familiar tropes.

On Thursday afternoon, a couple of hours after the Jim Lopes revelation, I flicked on the World T20 game between Bangladesh and Hong Kong. I wasn't paying a huge amount of attention until, with Hong Kong at 50-odd for 5 chasing 109 to win, I happened to glance up and see Munir Dar, like Omar Sharif playing a provincial police sergeant, who, to use Anthony McGowan's glorious euphemism, looks as though he loves his rugby. I'd idly assumed Bangladesh would knock over the last five wickets and win comfortably enough, but there was something in Dar's eyes and, more particularly, in the cut of his moustache, that said he wouldn't let this capitulation happen.

He was an archetype. Anybody who has played cricket at any level (in England, at least), knows the type. In my head, I filled in the details. During the week, he's a disappointed man, somebody who, at 40, is still just a low-grade manager in a sales firm. He dreamt of bigger things, but he knows now that he's hit his level. He's had experience in the Territorial Army, which is why he has the moustache. He's gone on the weekend survival marches, slept in the wild, defecated into a Tuppaware box so he leaves no trace. He might not be the best woodsman or map-reader or marksman, but he's tough: he never complains.

He has a sense of duty, so he does his sales job diligently if unimaginatively, clocking up the miles on the motorway. But what he really lives for is Sundays when he turns out for his local cricket team. He's not flashy but he is reliable. He can biff away in the middle order and bowl niggardly fingerspin that doesn't really turn. He's too hefty to run much, but put him near the bat and he'll unshirkingly get in the way, catching more than he shells. At least once a season, he'll dislocate a finger, strap it up and carry on playing in a manner that is ostentatiously uncomplaining.

What he loves most of all is marching to the wicket with his team in crisis, five down for not very many. Then the fire will glint in his eyes and the moustache will shimmer with intent and he'll block and push singles and finally cut loose and save the day. In the bar afterwards, he'll sit quietly, not speaking of his heroics, but desperately hoping others will, so he can dismiss their congratulations with a just-doing-my-job raise of the hand.

Which brings us back to Munir Dar, whose 36 off 27 balls - watchful and gritty, progressing to a glorious straight six - did inspire Hong Kong to an improbable victory, albeit only after his dismissal brought a late stutter. I know nothing of him. A quick Google search tells me he's 40, was born in Pakistan and that he is serving a 12-month ban for an iffy bowling action. The game against Bangladesh was almost certainly his final one at that level, which adds a one-last-mission gloss to his achievement.

But frankly, I don't want to know more. If this were football, I'd be tracking down his friends and family and those who had played with him, accumulating detail and writing facts. But this is cricket: I'm just a fan so I don't have to worry about all that; I can just imagine Munir getting back into his company car on Monday morning, heaving a heavy sigh, putting a selection of soft-rock classics on the CD player, firing up the SatNav and setting off for whatever Hong Kong's equivalent of Newport or Northallerton is. He'll show his merchandise, agree a deal, drink weak coffee in the bleakly clean conference room, never mentioning his knock but all the time praying somebody will ask him what he did at the weekend.