2018 Fifa World Cup Russia: VAR Technology

Football is getting used to the idea of video assistant referees (VAR), yet teams are already using technology to help players keep their eye on the pitch as well as the ball.

In Russia this summer, the referee - long lambasted as the footballing equivalent of Mr Magoo - will now be primarily the ‘on-field referee’. In a studio will sit another referee, the VAR, surrounded by screens that show replays from all cameras in the ground. The VAR can intervene if the on-field ref makes an error over a goal, a penalty award or non-award, a red card, or if a player has mistakenly been red-carded for an offence committed by another player. Away from the baying crowds, screaming coaches and nagging players, the VAR reviews the footage and, if necessary, advises the on-field ref to change the decision.

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The provision of a VAR system carried a number of challenges including making all broadcast angles available in real-time to the VAR and the operator in order to make decisions in line with the IFAB’s directive: “maximum benefit, minimum interference”.
Checking offside positions of players has proven to be one of the more difficult tasks due to the number of variables and the very short time-span in which the decision needs to be made. The exact pitch dimensions including any physical camber on the field as well as distortions of the camera lenses make it very difficult for a virtual line to be drawn that accurately represents a true straight line as it would be physically drawn across the field. In addition, with a large number of cameras to choose from, the provider must be ready to show the virtual offside line from the best possible angle in any given situation instantly.
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