Florian Wirtz’s goal for Liverpool on Sunday highlighted the biggest problem with the Premier League’s implementation of semi-automated offside technology.Photo by Justin Setterfield/Getty ImagesF...
Florian Wirtz’s goal for Liverpool on Sunday highlighted the biggest problem with the Premier League’s implementation of semi-automated offside technology.
Photo by Justin Setterfield/Getty Images
Florian Wirtz scored his second goal of the season in his 25th appearance for Liverpool on Sunday, but the strike wasn’t without controversy.
The TV images seemed to show Wirtz in an offside position before receiving the ball, with the lines on the pitch as a helpful indicator that the Liverpool player was slightly more advanced than the last Fulham defender at the point of the broadcast freezeframe.
Yet the goal was given, with the Premier League’s semi-automated offside technology ruling it onside. So what happened?
Image via @PLMatchCentre
For a start, it’s worth mentioning that the semi-automated offside system provides access to a slightly more accurate kick-point. That’s because their tracking cameras operate at twice the frame-rate of the broadcast cameras, so they’re seeing a different frame to those of us watching on TV.
Even so, Wirtz looked too far offside for such a small fraction of a second to explain why he was ruled onside.
Instead, the likely reason for that decision comes down to the Premier League’s choice to use a tolerance level, or a margin for error.
Photo by PAUL ELLIS/AFP via Getty Images
To put it simply, semi-automated offside technology isn’t perfect. It’s generally believed the system has a margin for error of a few centimetres, which could well be the difference between a player being onside and offside.
Unlike every other league, the Premier League decided that they would therefore allow any goals where the player was judged to be offside by 5cm or less.
That way, they’d never rule out a goal that was actually onside but appeared to be offside due to the imperfect technology.
The argument is that they’d rather incorrectly give some goals than incorrectly rule some out. But even if that logic makes sense, it comes with major drawbacks.
Photo via @FutOffsides and shows their assessment of Florian Wirtz’s goal vs Fulham
For one thing, we’re now in a situation where goals like Wirtz’s are given despite it being clear to everyone that they were offside.
It looked offside on TV, the technology likely knew it was offside within its tolerance level, the assistant referee gave offside only to be overruled, independent assessment has shown it to be offside (see above) and even Wirtz admitted he thought he was offside.
So it’s bizarre and confusing for supporters when the goal is given anyway.
It’s also just a strange way to officiate the game. It’s possible that the semi-automated offside technology would have given some incorrect decisions in one way or another without the threshold. But with the threshold, it’s practically a certainty that many wrong decisions will be made.
Imagine a scenario where a player is 10cm offside, but the technology incorrectly judges them to be 5cm offside (due to the system’s margin of error). Then, due to the Premier League’s threshold of 5cm, we allow the goal, despite correctly believing the player to be offside.
To put it another way, the worst-case scenario is now a 10cm error, rather than a 5cm error. It may feel nicer to give more goals, but it’s made the system twice as inaccurate in giving those goals.
Example of a semi-automated offside graphic (via PremierLeague.com)
On top of all this, the Premier League also have an issue with how they present these offside images to the public. Most semi-automated offside systems show the decision from directly in line with the player, making it easy to see the body part that strayed beyond the last defender.
But if the Premier League did the same, you’d see that the “onside” player within their tolerance margin actually appeared to be slightly offside.
To try and avoid releasing confusing graphics, the Premier League opted to show the decisions at an angle, effectively just hiding the fact they’re using a margin.
If they thought that would reduce confusion around offside decisions, those in charge at the Premier League should try taking a look at the last 24 hours of posts about offsides on social media.
No offside system is going to be perfect, that much is clear. But the Premier League’s implementation of their system has created the potential for larger errors and greater confusion among supporters, which seems very counter-intuitive.
Category: General Sports
