What is semi-automated offside technology and how does it work? | OneFootball

Semi-automated offside technology (SAOT) will be used in English football for the first time this weekend as it makes its domestic debut in the fifth round of the FA Cup.

Seven of the eight ties will utilise the technology, which is designed to improve the speed and efficiency of VAR checks around offside decisions.

SAOT has been used in the Champions League since the 2022-23 season, having also featured at the 2022 World Cup and Euro 2024.

The Premier League voted unanimously to introduce the technology last year, but its unveiling in English football has been delayed at various stages this season.

SAOT has been designed to provide a more efficient and accurate placing of the offside line, based on a picture generated by player tracking and 30 in-stadium cameras.

Under the previous system, the VAR would need to manually place a ‘marker’ on the relevant defender and attacker to produce two ‘lines’ and determine the ‘kick-point’.

SAOT will automatically create those points - and the Premier League hopes the technology would reduce the time taken for a VAR check by around 30 seconds.

Once a decision is made and approved by the VAR, a computer-generated graphic will be shown to the broadcast audience and fans in the stadium.

An example of the computer-generated graphic produced by semi-automated offside technology (FA)

There remains a human element to it, as the VAR may still have to make subjective calls in some cases, such as an offside attacker not touching the ball but interfering with play.

The Premier League have created their own technology with the PGMOL and provider Genius Sports.

It will only be available at the FA Cup ties being played at Premier League grounds, with Burnley’s clash against Preston the exception.