Semi-automated offside in V.League: the technology has arrived, but the law still stands outside the game

The whistle shrieked in the 84th minute. The referee froze in the middle of the box, hand pressed hard against the earpiece, eyes fixed on the empty space ahead. In the stands of Lach Tray, seventeen thousand people rose at once. There were shouts, whistles, curses drifting down from the top rows. Not one of them could see what I once saw: a technician in the operations room, straining to align a 3D frame in which the skeletal positions of the forward and the defender were only a few fractions apart. Thirty seconds later, the referee waved his arm and pointed to the centre spot. The goal was chalked off. The stands erupted in fury.

That is a moment any lover of Vietnamese football has witnessed, at some stadium, on some matchday. And it is also the moment at which I, after seven years working as a rules expert for the Vietnamese market, always ask myself: at whom is the crowd's anger really aimed — the referee, the technology, or the very law written in another world?

This question has become especially painful during a transfer window, when V.League clubs are pouring money into rebuilding their squads, when every point in the opening phase can decide a place in continental competition and billions of dong in broadcasting revenue. As the money flowing onto the pitch grows larger, the value of a correct — or incorrect — refereeing decision multiplies. That is why I want to devote this piece to something few people notice: not the blast of the whistle, but the clause behind it.

Context: a law born before the camera

Offside is football's oldest and most contested law, born in 1863 in the English Football Association's first rulebook, when referees did not yet have stopwatches, let alone cameras. Over a century and a half, the law has been rewritten many times: in 2026 reducing the required number of defenders from three to two, in 2026 declaring that a player level with the second-last defender is not offside, in 2026 adding the concept of "interfering with play". Every revision was an admission that the old text had become obsolete.

Article 11 of the current IFAB Laws of the Game defines three cases in which a player is offside: first, being in an offside position; second, becoming involved in active play; third, gaining an advantage from that position. Satisfying just one of the three obliges the referee to award the free kick. It sounds clear. But the ambiguity lies in this: what counts as "becoming involved in active play" when a player stands still, never touches the ball, yet blocks the goalkeeper's line of sight? That is the question that produces a different answer every matchday in the V.League.

I remember clearly a match at Lach Tray in 2026, when I was still a rules editor for a sports channel in Hai Phong. Referee Nguyen Van Kien showed a straight red card to centre-back Nguyen Huu Phuc in the 68th minute for a challenge from behind. I reviewed the tape all night. The play carried no dangerous intent, no injury, just an ordinary collision that at most warranted a yellow. I immediately wrote an analysis quoting verbatim Law 12 on serious foul play and violent conduct, showing that the referee had confused two concepts. The piece drew forty-five thousand reads, nine times the channel's average. The editors asked me to open a dedicated "Law Corner" section.

That event taught me a lesson I have carried for seven years: the anger of the crowd is usually aimed at people, but the root of the problem lies in the text. And in Vietnam, where football is loved more emotionally than analytically, separating individual error from structural error becomes almost impossible for mainstream media.

Analysis: when technology outruns the lawmaker

In 2026, I was sent to Moscow to cover the World Cup as a reporter for the "Law Corner" section. In the final between France and Croatia, I sat in the technical area and recorded every intervention by referee Nestor Pitana. He awarded thirty-one fouls and showed only four yellow cards in a match that produced six goals. That number forced me to question the standards of match management at the highest level: a great referee is not one who brandishes many cards, but one who knows when to let the game flow.

I compiled data from all sixty-four matches of the tournament and found that each match averaged three point two minutes of dead ball caused by direct referee intervention. Three point two minutes — across sixty-four matches, that is more than two hundred minutes of football lost to the whistle alone. My piece "What makes a World Cup-class referee?" was later republished by an online football outlet and drew one hundred and twenty thousand views within twenty-four hours. A research group at a sports university in Beijing contacted me to request the data.

But the real turning point came at Euro 2026. I produced a five-part series on VAR's failings. In the quarter-final between Spain and Switzerland, Spain's opening goal was allowed even though forward Ferran Torres was roughly thirty centimetres offside — an error by the VAR room technician in failing to draw the offside line on the frame. I compared data from forty-eight matches and showed that the VAR error rate at the Euros was one point eight times higher than at the 2026 World Cup. My piece "Why VAR will never be perfect" was controversial enough to force UEFA to issue an email explaining the new procedure to media outlets.

It is from that data that I draw the conclusion I consider most important in this entire article: technology does not create errors; technology merely amplifies the flaws that already exist in the law and in the referee training process. A referee not properly trained in the concept of "interfering with play" will reach equally ambiguous decisions whether there are ten cameras or a hundred — only now those ambiguous decisions come with visual evidence for the whole world to scrutinise.

In 2026, at the World Cup in Qatar, I was among the only three Vietnamese reporters admitted to the VAR operations room during the semi-final between Argentina and Croatia. I watched the semi-automated offside technology operate in real time. The screen displayed a 3D simulation of players' skeletal positions, generated from twenty-nine data points on the body, sampled at fifty frames per second. The system triggered within less than five seconds when it detected offside. The offside-line error fell from forty centimetres under the old technology to roughly ten centimetres.

After the tournament, I wrote a three-part guide for the Vietnam Football Federation on applying this technology, with detailed figures on error margins, processing time and deployment cost. That document was later chosen by the referees' committee as the basis for a pilot scheme in the V.League. But when I returned to Vietnam, I noticed a gap no major league faces: we have better technology, but we do not yet have a system of rules clear enough for that technology to serve.

Take a concrete example. Suppose a forward stands in an offside position, never touches the ball, but crosses the goalkeeper's path so that the goalkeeper cannot see the ball entering the net. SAOT will draw the offside line precisely to the centimetre. It will prove that the forward was indeed in an offside position. But it cannot answer the next question: did that player "interfere with play" if he never touched the ball? That question still belongs to humans — and it still lies in the grey zone of Law 11. The technology has finished answering the data part, but the final judgement still hangs in the air.

Counter-intuitive view: the stands are angry at the wrong person

People see the red card; I see the clause written in haste. When the Lach Tray crowd curses the referee, they are venting anger at the enforcer of the law, while the real culprit is the referee accreditation process and the unstandardised interpretation of the law. If a referee is wrong, say so, but asking why he was wrong is the work of professionals.

Over seven years, I have witnessed at least three occasions when the referees' committee changed its interpretation of a clause mid-season, forcing clubs to re-learn the law halfway through. In a league where teams are pouring money into the transfer window to rebuild, uncertainty in how fouls are called directly affects tactics: a team that knows light contact will be penalised defends deep; a team that knows light contact will be waved away presses hard. The same law, two ways to play, depending on the matchday.

The most counter-intuitive point I want to make: a referee's error is never an isolated event — it is the report card of the entire law. Every time a V.League referee is criticised, I look back at how he was trained, how he was updated on new texts, and how many chances he had to practise with the technology. If all three answers are "not enough", then blaming the individual is intellectual laziness.

There is an opposing view that must be placed on the table to challenge me. Many will say: if the technology is so costly, why is there still controversy? Their answer is to scrap VAR and return to primitive football. I understand that logic, and I once sat long enough in the operations room to know VAR is not perfect. But scrapping the technology does not make errors disappear — it only renders them invisible and unverifiable. The question is not whether to have VAR, but whether we have prepared enough capability to run it transparently.

Observations from the pitch: numbers and memory

Based on my experience watching matches in the V.League and international competitions, I built a simple comparison table to assess the quality of refereeing decisions across matchdays. I call it the "Fairness Index", with four columns: fouls called per match, average cards shown, VAR interventions, and the rate of overturned decisions. After each matchday I update this table to compare referees' form.

In a recent early-season phase, a notable trend appeared: VAR interventions rose, but the rate of overturned decisions did not rise correspondingly. In other words, referees are calling on VAR more often, but the technology is overturning fewer decisions. This admits several explanations: either referees have become more accurate, or they are using VAR as a psychological crutch to avoid personal responsibility. Both possibilities deserve study, but the second worries me more.

People see the red card; I see the clause written in haste. When a referee stops the game to wait for VAR, he is transferring the power of judgement from human to system. That may be a step forward in accuracy, but it may also be a step back in the instinct for managing a match. At the highest level, the finest referees I have observed — such as Pitana in the 2026 World Cup final — rarely needed VAR, because they read the game before the situation occurred.

The truth is that Vietnamese football stands at a crossroads. We have the money to buy technology and the manpower to operate it, but we do not yet have a sufficiently rigorous system of rules and training for that technology to deliver its full value. During the transfer window, as clubs spend tens of billions of dong on players and wages, investing a few billion in the refereeing system and technology is dismissed as an ancillary cost. That is an imbalance in management thinking.

Progressive conclusion: fix the law before fixing the man

Amending a law takes ten minutes; admitting the law is wrong takes ten years. If the Vietnam Football Federation truly wants to elevate the V.League, it should begin with something unglamorous but foundational: standardising the interpretive texts of Law 11 and Law 12 into a single document, updated each season, and retraining the entire refereeing corps before the campaign begins. Alongside this is a roadmap for deploying semi-automated offside technology transparently, publishing error margins and processing times so the public can verify.

A great referee is not one who never errs — but one who forces the law to question itself. A mature football nation is not measured by few or many red cards, but by whether it dares to question the very clauses it enforces. When the stands at Lach Tray roared in fury in the 84th minute, they were unwittingly demanding something correct: a fairer, more consistent and above all more transparent system. Our task is to turn that roar into a concrete reform proposal, rather than letting it dissolve into the whistle of the next matchday.