Graphic: On the spot

Well, we’re right down to it now. The semis of Euro 2008. And I thought the players who remain may appreciate a little advice. In case things get sticky.

How do you prepare for a penalty shoot-out? Well, you can practise, I suppose. If you insist. But you should also try to read a book, work out how to understand a graph and learn how to manipulate an Excel spreadsheet.

With the help of the data collected by Castrol as tournament sponsor, the Fink Tank is going to explain exactly where to place a penalty. First, you divide up the goal into zones. David Kerwin and Ken Bray have analysed video footage of penalties to work out the area of the goal that the average goalkeeper could conceivably reach when a penalty is taken.

The time it takes a penalty to reach the goalline is half a second and the goalkeeper’s reaction time is about a quarter of a second. Therefore, to maximise his chances of saving, the goalkeeper must begin to dive (if he chooses to dive) before the penalty is struck — if he waits until the kick is taken, it will be halfway to the goal before he can move. Bray’s research showed that there are areas of the goal where the ball is “unstoppable”, even if the goalkeeper dives early.

Second, you need to take three years of penalty statistics and look where the ball went. From this you can see what happens on average when you shoot the ball into different zones of the goal.

Fortunately, this work has been done for you. We have looked at 1,513 penalties taken in big competitions. Of these, 80 per cent were saveable and 77.7 per cent of these saveable penalties resulted in goals. This is naturally less than the proportion of unsaveable penalties that result in goals.

The problem is what happens to penalties that are aimed into the unsaveable areas. They often miss or hit the woodwork. This leads to the third lesson: realise from this data that you are making a trade-off and how good you are at penalties should influence this. The graphic provides a helpful ranking.

Finally, the timing of the penalties is important. The optimum moment appears to be between the 60th and 75th minute. After that the success rate of penalties declines, perhaps because of tiredness. This suggests that bringing players on for a shoot-out works, but it is better if they have warmed up first.