Question Number: 33500

Law 11 - Offside 7/3/2019

RE: Rec. Adult

Bevan Burgess of Ipswich, Suffolk UK asks...

Regarding VAR and offside. How do the VAR operators chose which TV frame to choose for measuring whether a player is offside or not? I understand that it should be when the player kicking the ball first touches the ball, but do they have the resolution of image to check for first contact, or is it a 'best guess'?

Answer provided by Referee Joe McHugh

Hi Bevan
In addition to the normal TV cameras there are also offside only cameras being used by VAR. There is also a Hawk Eye system in place
Virtual offside lines are computer-generated lines projected onto the broadcast image of the field of play to help the VAR determine whether an offside offense has occurred. The offside lines used are the best possible and most accurate lines that can be generated with existing technology due to calibration using multiple synchronised camera angles.

Virtual offside lines are superimposed on the broadcast image by computer software. Angle of view, lens distortion, field curvature and many other factors are considered when calculating the true position of the these lines. The lines are calibrated before each match by the technology provider to take into account the exact pitch dimensions and conditions on the day. The VAR team will have various tools available for determining offside positions, which have been validated in a number of tests across different venues by an independent third party using survey grade equipment.
You can watch the technology being tested by FIFA in this video
https://www.youtube.com/watch?v=PCOK7-kc_8o&feature=youtu.be
With modern HD video technology the picture is freeze framed at the moment of the touch. That is a judgement call like in the image at 3.47 of the video. Technology is accurate and unforgiving
In the England V USA game the consensus is that it was offside and that was proved by technology. When I saw it in real time I said offside and it did not surprise me when it was ruled out.
It was a tight call yet no complaint can be made. Without VAR the penalty in my opinion would not have been awarded.

Answer provided by Referee Peter Grove

Hi Bevan,
According to the information released by FIFA, the VAR team has access to 33 different broadcast feed cameras. Included in those are:

''eight super slow-motion cameras, four ultra slow-motion cameras, two ultra high-definition cameras, and two offside cameras.''

So as far as I can tell, the VAR team has more than adequate technology to determine the exact moment (frame) that shows the precise moment the player first touches the ball, and then to use it to judge the position of any player who might potentially be guilty of an offside offence.

Answer provided by Referee Richard Dawson

HI Bevan ,
on the front page of our site was the idea of how VAR was to be implemented
VIDEO ASSISTANT REFEREE
How the VAR will work. Check out it, it's an interesting setup. They're putting a lot of work into it.
https://www.youtube.com/watch?v=YdwOL08NfxQ

Here's a video on how they'll be doing the VAR line looks like, unlike what a lot of us see on TV, it'll try to take into account the head/chest/shoulder and not just the feet
https://www.youtube.com/watch?v=PCOK7-kc_8o