Cup about to get even hotter

The knockout stages of the World Cup bring new challenges for players and coaches. Tactical decision-making becomes increasingly significant as the stakes rise.

Fitness and the ability to keep the best possible starting XI on the field become differentiators between success and failure. Add the prospect of 30 minutes of additional playing time in hot and humid conditions, plus the mental burden of imminent penalties, and the Brazil tournament, so entertaining to date, is about to assume a much more suspenseful cloak.

All these challenges were demonstrated by Brazil and Chile in a furiously fast-paced match that culminated in every supporter's worst nightmare, the penalty shoot-out. Much to the relief of the hosts (and, I would suggest, the neutral world, for the benefit of the tournament), Brazil scraped through and move on to a clash with an enterprising Colombia.

It has been a South American affair. Of the 10 teams from the Americas (South America and the Concacaf region), eight reached the knockout stages. Compare that with Europe, with only six out of 13. The way the draw has worked out will ultimately skew this balance, because the South American teams are set to eliminate each other - two are out already by their own continent's feet, and Brazil vs Colombia will further reduce four into one by the semifinals.

Many have attributed this dominance to the so-called continental home-ground advantage. That is, no European team has ever won a World Cup in South America, and the only South American team to win in Europe was Brazil in 1958. I've written about home-ground advantage before, and explained that much of it exists because referees are sub-consciously influenced by the cheers and appeals of thousands in the crowd, and thus make decisions that benefit teams with the loudest support. Other typical explanations are the cultural and language familiarity of being closer to home.

A bigger factor, in my opinion, is that some European teams have underperformed, mostly because they have relied more heavily on ageing players whose significance to club teams has left them fatigued and with nagging injuries (I'm thinking mainly of Spain, Italy and Portugal). Fewer South American players are as heavily relied on in Europe. This phenomenon has been observed before, including in 2002, when European nations underperformed to such an extent that Uefa changed its calendar to reduce the number of matches in the Champions League.

Another factor at this World Cup is the heat. Many commentators have suggested that the South American players are better able to handle the hot and humid conditions. The only problem with that theory is that most of the South Americans play in Europe anyway - 16 of Colombia's and 19 of Brazil's 23-man squads are Europe-based, for example. Physiologically, we lose our adaptation to the heat within a few weeks, and so all those players, coming off a European winter, are no better off than their European rivals.

So far, the heat hasn't obviously affected matches, at least not dramatically, as it has in other events such as tennis's Australian Open earlier this year. The problem for footballers is not really safety, however, but performance. Considering that the average player runs about 10km and makes about 100 sprints during a match, what you'll see in the heat is a progressive slowing down of the game.

Now, with extra time a possibility, teams will lack even more than before the physiological ability to go forward with real intent. I'd predict that not many goals will be scored in extra time at this World Cup because that fatigue will cause teams to revert to more conservative tactics and push forward less, and most extra-time games will be shut down. After all, who wants to make the mistake of costing their team with a glaring error?

Whatever happens, the suspense is about to be ratcheted up, and penalties are bound to decide a few more matches. They are an entirely separate proposition, for discussion next time. Until then, enjoy the drama.