The goalkeepers at next year's World Cup in South Africa better consider their geography before getting on the field.
A new study done by Adidas shows that altitude at the World Cup will have an impact of up to five per cent on a ball's speed. That means, according to the study seen by The Associated Press, that a free kick from 20 yards during the final at the Soccer City stadium in high-altitude Johannesburg will reach the goal line five per cent faster than it would at the Moses Mabhida Stadium in sea-level Durban.
The translates into a free kick travelling at an average 126 km/h at high altitude or 120 km/h at sea level.
But if playing at high altitude has some drawbacks for goalkeepers, it also has its advantages. A goal clearance that travels 60 yards in Durban will travel 63 yards in Johannesburg. And even more importantly, free kick specialists will not be able to put as much spin on the ball because the thin air offers less resistance to change course.
Among the nine host cities during the World Cup, Soccer City stands at 1,694 metres. The beach-side Moses Mabhida Stadium is at only eight metres.
Other stadiums higher than 1,000 metres include Bloemfontein at 1,351, Pretoria at 1,330, Polokwane at 1,230 and Rustenburg at 1,153. Apart from Durban, Cape Town and Port Elizabeth are also coastal.
Even more important than the speed of the ball will be the speed of players adapting to the different altitude levels. To get an edge, most of the major teams have already decided to set up camp as high as possible, mostly in and around Johannesburg. It is easier for players to adapt coming down to sea level rather than moving up to high altitude.
Reliable ball promised
Adidas traditionally produces new balls for each World Cup and they invariably cause controversy, since new technology almost always makes for a speedier ball that puts goalkeepers at a disadvantage. Keepers have complained that some balls also wobbled on long-distance drives, making them look foolish on some goals.
This time, Adidas is convinced the Jabulani, which means "to celebrate" in isiZulu, will sail true because small dots on the surface improve reliability in the air for "an exceptionally stable flight and perfect grip under all conditions."
For the fans, the new ball is a splash of colour compared with the black-and-white Teamgeist ball used at the 2006 World Cup in Germany.
Adidas said the 11 colours not only represent the players on a team's starting lineup but also the 11 official languages and the 11 communities of the host country.
World Cup lore shows that maybe the ball does matter. At the maiden World Cup in 1930, Argentina and Uruguay supposedly could not agree what ball to use, so they compromised and used a different ball in each half.
With its ball, Argentina raced to a 2-1 lead at halftime. But the Uruguayans bounced back with their ball and won the final 4-2.