At first, it did not strike Winfried Schaefer, Cameroon's coach, as unusual. How could it?
Marc-Vivien Foe - tall, strong, "like Schwarzenegger" - was one of his key players, an on-field leader. A stomach complaint had forced Foe's withdrawal after an hour against Turkey in the 2003 Confederation's Cup in France. He was rested for the subsequent game against the United States as Schaefer, who has coached both Al Ahli and Al Ain in the Pro League, experimented with his squad.
Then, preparing for the Colombia semi-final in Lyon, where Foe spent a popular couple of seasons, Schaefer asked him whether he was fine to play.
He said he was.
On match day Cameroon were leading 1-0 at half time, when the team doctor went through the players, reporting no concerns.
Twenty minutes into the second half, thinking of substitutions, Schaefer asked his doctor to check on Foe. Again, he said he was fine to continue.
"Five minutes later, he lost the ball and came to the centre circle," Schaefer said in a telephone interview from Thailand where he is the national team coach.
"Now, I don't know, as the ball was somewhere else, nobody saw Marco go down. One defender started shouting for the doctor and when he ran on, the referee - who hadn't seen Marco - shouted at him asking what he was doing."
The game stopped. Foe was carried off on a stretcher. Schaefer, unperturbed, went to check on the sidelines.
"I go to his face, with my hand and say 'OK, Marco, come on, come on. No problem.'
"I go back to my bench and the match continues."
Later, the players celebrated their win in the dressing room and prepared to go for a warm-down jog. Rigobert Song, the captain, suddenly came back in crying. Schaefer recalls him saying: "Marco's dead."
"It was like a bomb in my head, I cannot tell you," Schaefer said.
"I left to be alone and I go into one room where a young boy was playing football and then another where I hear lots of crying. In this room was his mother and wife. Marco was in there. I went to him, touched his neck, went out and cried."
Fabrice Muamba's recent fall came close to being the bomb in the head Schaefer spoke of. Even though the Bolton Wanderers midfielder is recovering, it remains difficult to grasp why, in relatively low-contact sport with rare, heightened levels of fitness, a young man just falls over.
The suspicion of several medical practitioners is Muamba has hypertrophic obstructive cardiomyopathy (HOCM), a genetic disorder that causes the wall of the heart to become thicker than it should and disrupt the normal flow of blood to and from the heart. The first symptoms - a cardiac arrest - can often be, unfortunately, the last.
Yet there have been enough such incidents on the football field for it to be asked whether footballers are somehow more prone.
"There's no association or reason why this should happen more with football," said Luke Anthony, the physiotherapist at the English Championship club Reading.
"Generally speaking they are genetic defects. As there's more people playing football than any other sport. It's probably related to that."
Peter McBride, the chairman of the trustees of the Cardiomyopathy Association, a leading charity, also plays down the notion.
"It is not relevant. It affects any age of the population any time and it can be athletes or non-athletes."
Are African players more at risk? In these pages, Ian Hawkey listed at least nine professionals from Nigeria, Chad, Liberia and Zambia (and Cameroon's Foe) to have died from heart failure while playing, since 1989.
Additionally, a number of players have had heart conditions discovered only once they started playing in Europe.
Hawkey also cited the results of a Fifa-backed medical research team which found that "black African athletes seem to have an increased risk of adverse cardiac events during sports events," after a survey conducted at the 2009 African Under 17 championships.
"Footballers, particularly from sub-Saharan Africa, are thought to be at a increased risk of heart failure," confirmed Nick Wilford, a doctor who works with Norwich City.
"Risk factors in Africa which increase heart-failure risk include hypertension, cardiomyopathy and rheumatic heart disease. Cardiomyopathy is commonly genetic or endemic in Africa."
Though Wilford is not a cardiologist, he adds that Africans who move to the West are at particular risk, layering on to underlying genetic factors the possibility of ischaemic heart diseases (blocked/narrowed coronary arteries brought on by dietary and lifestyle factors and which are more common in the UK).
To this, the natural response has been to call for an increase in the screening of players. Currently, all players in England, for example, are required to be screened at the age of 16. "That involves an echocardiogram [ECG], and an ultrasound scan of their heart.
"If you're clear on those, that's pretty much all you can do at that stage," Anthony said.
"There's no real set rules thereafter. Some clubs screen every year. Otherwise, it'll be when players go from club to club in pre-signing medicals."
Manchester City's manager Roberto Mancini has called for more screening, drawing from Italy where players are screened twice a season.
In the UAE, where Al Nasr's Salem Saad collapsed and died during training in 2009, Al Jazira organised echoes and electrocardiograms (ECGs) on first-team players as well as on the U17 team.
"The Pro League are looking to adopt a similar thing over the next year or two," said Nick Worth, Jazira's physiotherapist.
"The Asian Federation have brought in a regulation which means twice-yearly people will be having echoes and ECG screenings, across all clubs that qualify to play in the Asian Champions League from next year."
But it is not so simple as more screening and, thus, more detecting mean the financial implications of an increase are vast as well.
Detecting cardiomyopathy, for instance, even for a cardiologist as McBride illustrates, is not easy.
"We do a conference for cardiologists each year in London," he said. "In one of the sessions a leading cardiologist will put up an echogram. He'll ask the others what do you see and they'll say definitely not cardiomyopathy.
"He'll move it a fraction and they'll say it could be this, but not cardiomyopathy. Then he'll move it a fraction more and they'll realise it's cardiomyopathy.
"And these are people interested in the subject. My hero cardiologist says there is only one rule about this, and that is that there are no rules."
One inference is that more than quantity, it is the quality of screening that is important. Are cardiologists screening players, asks McBride and, if so, are they looking for conditions such as cardiomyopathy? Are screenings comprehensive enough?
"In the first instance, a thorough history should be inquired when signing a player," Wilford said.
"Any family history of premature cardiac death should set alarm bells ringing. There is little doubt in an ideal world all players would have regular echocardiograms and ECGs and, conceivably, the more frequent the safer, although of course increasingly unlikely with increasing frequency to result in positive findings.
"Cardiac MRI might also be useful as not all cardiomyopathies are found on echocardiogram."
Yet, inevitably, some slip through: "Sometimes these things still just happen," as Worth said.
Then, on-field medical aid and staff need to be as well-trained and efficient as they were at White Hart Lane, where Muamba collapsed. The standard facilities - defibrillators, resuscitating equipment, pitch-side doctors and ready ambulances - are increasingly found at most football clubs, including the UAE.
"If you're going to have a cardiac event, a football ground is probably the safest place outside of a hospital to have that," said Anthony, who undertakes annual training courses to deal with precisely such situations.
Last December, Schaefer was at a game in Thailand when a player suddenly keeled over. It was hot as Schaefer watched, disbelieving. The player turned out fine, suffering from dehydration.
But, briefly, Schaefer was reminded again of vulnerability. "It was the same situation." he said.
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