Could an unlikely hero save football from VAR?

But she is also a football fan whose West Ham season ticket gave her a front row seat for an innovation that has, without doubt, changed the game - and that has now inspired a fascinating and persuasive new book.

“I was at the very first VAR decision in the Premier League. It was Raheem Sterling offside for Man City against West Ham, although we lost five-nil anyway, so it wasn't particularly decisive.”

Although she had anticipated problems with the new system, she says that she was “sort of cautiously optimistic about it”, not least because it has been very effective in other sports like cricket and rugby

“And so you just felt like okay, this is the next step. And obviously the goal line technology worked really well.

“So it was really kind of astonishing to me that [VAR] wasn't working, and all the reasons why it wasn't working, and I genuinely couldn't stop thinking about it – so that's where the book came from.”

So what does she think are some of the main problems with VAR?

Well, it has massively complicated some aspects of football, such as hand ball – the rules for which are now eleven times longer than they used to be. The use of slow-motion replays and pitch-side monitors, which have psychological effects on referees that are influencing the outcome of games, is another issue. Human error and inconsistent processes remains a significant problem.

The combination of these, and other, issues, all rooted in attempts to introduce asynchronous technological reviews to a sport whose rules were designed in a world where such things didn’t exist, have resulted in disruption to what Christodoulou calls the “flow of the game.” As a result, the way in which we understand and experience football itself is being changed.

Put simple, in a doomed attempt to perfectly apply the letter of the laws, something about the spirit of the game has been lost.

But lots of people say the same things, see the same problems, and lament the same consequences. There’s no shortage of football fans who, even if they can’t list specific incidents, just feel that something has gone wrong, and that VAR is part of it.

What makes Christodoulou different is her ability to break down the specifics in truly fascinating ways and to express hugely complicated concepts in simple, engaging language.

The clearest example of this is her utterly brilliant explanation as to why an aspect of VAR that feels like it should be a straightforward, black-and-white decision – whether or not a player is standing in an offside position – is actually, both at a mathematical level and in terms of its impact on the game, devilishly complex.

She uses that example of the Premier League’s first ever offside call, in which Raheem Sterling was “deemed by VAR to have been offside by 2.4 centimetres.” But is the system really that accurate?

Christodoulou points out that VAR cameras operate at a rate of “one frame every 0.02 seconds.”

The problem is that the camera has to be paused the instant the ball is passed to Sterling, which in this case meant freezing the frame the moment David Silva’s boot made contact, but in reality “this might have happened somewhere in between the two frames.”

If Sterling had been moving at 15kph (about half his top speed) then that works out to “about 4 metres per second, which is about 8 centimetres every 0.02 seconds”, leaving us with a margin of error that is more than three times the size of the distance by which the player had been judged offside. Factor in a defender running in the opposite direction at the same speed and the margin of error doubles.

Raheem Sterling was judged to be offside by just 2.4cm - much less than the technological margin of error (Image: BT Sport / TNT Sports)

This means that there are lots of calls in which, even if the whole system works perfectly, we don’t actually know for sure whether or not an attacking player was offside. That feels like a pretty massive problem when the whole point of VAR is to provide greater certainty and accuracy around decision-making in football matches. If we’re not even getting the certainty we thought we were, what on earth is the point?

But the technical and mathematical margins of error aren’t even the biggest concern.

For Christodoulou the football fan, the big problem is that VAR has fundamentally changed the offside rule by making it “more defence-friendly” and “reversed the trend we’ve had for 20 or 30 years.” It’s not the complaint of a technocrat who loves measurements and spreadsheets, but one of a fan who loves the game of football.

“It's basically changed the way we interpret the rule," she says. "It's the same with handball."

"There are a lot of offside decisions which absolutely, by the letter of law, they are right – but they have caused a lot of controversy. If you were an alien looking at it you’d say: 'Well why is that a problem? It's the right decision.'

But, she suggests, it’s actually much more complicated than that, even though officials would claim that those ‘letter of the law’ calls are in fact a sign of success:

"They'll say: 'Well that was a decision that was wrong in the past and it's now right and that's an example of us getting more right decisions.'"

"You've got more 'right' decisions, but everyone's unhappy.”

Ultimately, Christodoulou believes that VAR has been problematic enough for its use to be halted so that a proper, rigorous round of testing and evaluation can take place outwith the confines of high-stakes professional sport.

What we need, she argues, is a ‘Football Lab’ where player challenge systems, and even something she refers to as a Foul Probability Index, which would use comparative judgement technology to give an indication of the likelihood of an incident being seen as a foul, could be properly tested.

“I’d pause VAR for two years and try to develop something different and  have a proper pilot.

“This is one of the things I think you could learn from other sports like cricket and rugby – I think they have got better processes for trialling new ideas. I think VAR was always very top down and all the changes to it have been kind of in-season tweaks. That they've never really tried something completely fundamentally different as cricket did.

“So, I think it would be really good to experiment with some really different formats, and to do so in a kind of low-stakes league, that could be televised so that people can watch it and feel involved with it.”

“My gut instinct is that it wouldn’t work, but I’d love to see it trialled.”

I Can't Stop Thinking About VAR is now available in hardback (£14.99)