Anyone who's into football will be well aware of the massive emigration of talented soccer players from Argentina (which I dub "leg drain"), but the sport seems to be doing just fine in the country nonetheless. There is also a persistent "brain drain" of our most talented young scientists and the state of our science is dismal. Why the difference? Why in one case does emigration appear to be for the better, but in the other it is for the worse?

Let us tackle the players' case first. When a team wins either of the two first division soccer championships in Argentina it is highly likely that its most outstanding players will be sold immediately, usually to European clubs. Why? Have the clubs lost their interest in winning any further leagues? No. Instead, club officials are tempted to cash in on the increased value of their players; put simply, they sell high what they bought very low.

For the poorer clubs this comes as a windfall. For the richer, the dilemma is whether to sell, cash the money and train a new generation, or keep the players but raise their salaries. Given this choice it is hardly surprising that soccer stars end up leaving the country. Not all of them, of course. Roughly 30 players are sold annually out of a pool of some 400 first division soccer players. Nevertheless, Argentinean soccer is one of the top five in the world. This begs the question: why doesn't this leg drain affect soccer in the same way that the brain drain affects science and technology?

For a start, taxpayers are not responsible for the "education" of a soccer player. There are no national programmes devoted to the art of football. Instead, this is left up to the player's own interest and the foresight of his parents in predicting a footballing genius. From a young age the boy's talent is nurtured, and by the time he enters the soccer scene (around his 18th birthday) he is at the peak of his potential. If he is lucky he may delight crowds until he reaches the age of 35, when the wisest players retire. If he's sold abroad a new youngster will be brought in and trained up, no doubt spurred on by the possible fame and fortune that awaits him. This last point deserves emphasis; Argentina can afford to lose so many good players each year because there is so much talent available from which to select replacements.

So what happens to researchers? From a cynical perspective, a scientist is someone who discovered during his or her basic schooling a talent to perform abstract thinking, and subsequently decided to make a living out of this skill. Argentina, through its public education system, reinforced their hopes by providing good quality education at very low cost to the individual (though not to the country). But unlike their soccer counterpart, this 'scientist' is far from ready to perform on leaving college. Another five or six years of graduate school – and even more years of informal education spent honing their specialisation – will pass before she or he can contribute to the local scientific scene. Does this really matter? Let us see.

Argentina has some 12,000 researchers. If we assume that each individual's productive lifespan is 30 years, the country needs to recruit 400 researchers per year just to maintain the status quo. But if a further 200 scientists are lost to foreign countries for even just a limited period – as is currently happening – there will be a significant gap in the human infrastructure of local science. And unlike soccer, this cannot be easily replenished with fresh talent, because the training is so long and because the individuals have become highly specialised. With the loss of such a substantial proportion of researchers the scientific scene inexorably deteriorates, potentially to a point of total collapse.

Should Argentina be looking to its overseas scientists for help? Possibly. But the fact is that by and large, these scientists do not play a significant role in science back home. After all, research conducted abroad is usually in response to the scientific agenda of the country where the scientist is employed and is likely to have little or no impact locally. And unlike the simple and universal resources required for soccer, science rests heavily on specialised equipment that is scarce in developing nations.

Letting the best go has had a positive impact on Argentinean soccer. In science it has sadly been the opposite.