This is how the semi-automatic offside worked

He goal disallowed for offside against Robert Lewandowski against Real Sociedad has gone around the world. Only a small part of the boot of the Polish striker was enough for the team’s machine semi-automatic offside signal illegal positionalthough to everyone’s eyes it seemed to be in the correct position. Following the image many questions have arisen How does this machine work? How many cameras does it consist of? Where are they located? What is your margin of error?

Offside technologyor has premiered this season at LALIGA as a tool that came to put an end to all doubts about offsides in a radical way. Hawk Eye is the company in charge of the tool, having a contract with the competition chaired by Javier Tebas for the next four seasons. FIFA and UEFA, which have been using this technology since 2021, wanted a precise and quick response to speed up decision-making in offside situations.

This is how the semi-automatic offside technology that annulled Robert Lewandowski’s goal works

He SAOT (English nomenclature for the multi-camera technology that tracks the footballer’s limbs and establishes the exact moment of the pass) is made up of between 10 and 12 cameras (depending on the match), all of them located on the roof of the stadium and capture the movement of all the players on the field and also that of the ball.

The semi-automatic offside cameras are totally independent of the television broadcasting of the match. and they capture 29 different positions of a footballer’s body up to 50 times per second. Then, software analyzes the databeing able to calculate the exact position on the field to determine whether or not there is an offside in a play.

This technology has an average execution time of 25 secondsalthough it may be even lower if the position is quite clear to the machine. Like all technology, the tool does not act alone. The VAR room referees are the responsible for selecting the exact frame which corresponds to the player’s first contact with the ball when making the pass. And from there, the machine acts by drawing the lines between the defender and the attacker. Once the machine offers its analysis, the referees in the VAR room convey the final conclusion to the referee.

Based on the images collected by up to 12 cameras located on the stadium roof, the tool offers a 3D recreation of the play that is offered in the transmission of the game a few seconds later.