The paper, published in scientific journal PLOS ONE (details below), reports the results of tests using a specially developed virtual reality goalkeeping simulator, showing that stopping a free kick in football is harder if the goalie’s initial view of it is blocked by a defensive wall.

Dr Dessing explains: “While the defensive wall strategy is effective in some cases, the wall frequently obstructs the goalkeeper’s initial view of the moving ball. Although the negative effects of this obstruction have been assumed by experts, they have not been scientifically quantified until now.

“Our study showed that when the view of the ball is initially obstructed, goalkeepers wait longer before starting to move, which leaves less time to get in between the ball and the goal. Critically, this meant they did not get as close to the ball and that they were thus less likely to make a save.”

Across a four-month period, three experiments were conducted, involving 10 expert goalkeepers and 45 novice goalkeepers in total, all completing a 90-minute session.

This project was funded by the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 754507.

Full details of the paper:

Valkanidis TC, Craig CM, Cummins A, Dessing JC (2020) A goalkeeper’s performance in stopping free kicks reduces when the defensive wall blocks their initial view of the ball. PLoS ONE 15(12): e0243287. https://doi.org/10.1371/journal.pone.0243287

Find out more about the experiments here.

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