The Ball, Digital Avatars, and the Next Generation of Semi-Automated Offside

At the heart of the tournament's technological infrastructure is the evolution of the Semi-Automated Offside Technology, a system that combines tracking cameras installed beneath stadium roofs with real-time data transmitted by the official Adidas Trionda match ball. During the 2026 World Cup, every stadium was equipped with 16 high-resolution cameras dedicated exclusively to this purpose, compared with only 12 during the 2022 tournament in Qatar. These cameras simultaneously tracked up to 29 body points on every player multiple times per second.

The Trionda ball, named after the tournament's three host nations, contains an inertial sensor developed jointly with the German technology company Kinexon. The sensor records the ball's movement 500 times per second and transmits this information directly to the Video Assistant Referee (VAR) system.

Before the tournament began, each of the 1,248 qualified players underwent a full digital body scan, producing personalized three-dimensional avatars capable of reconstructing the precise position of every part of a player's body during any contested moment. By combining data from the ball with the positions of these avatars, the system can now detect offside infringements as small as 10 centimeters, compared with the 50-centimeter threshold effectively used four years earlier.

The resulting accuracy is dramatically higher—but perhaps too precise for what the human eye can perceive or intuitively accept as fair. A difference of only a few centimeters, impossible to detect at the speed of play, can now invalidate a goal that appeared perfectly legitimate to spectators in the stadium or watching on television.

This tension became particularly evident during a group-stage match when a stoppage-time goal scored by Colombian defender Davinson Sánchez was ruled out for offside. Television viewers were shown the player's own digital avatar, revealing that he was offside by little more than the tip of his boot. Fans challenged the referee's decision, yet few questioned what the technology itself displayed: instead of merely seeing a whistle blown and a flag raised, audiences could see the exact 3D avatar and virtual offside line that formed the basis of the decision.

Football AI Pro and the Democratization of Tactical Analysis

Beyond officiating, perhaps the tournament's most ambitious innovation is Football AI Pro, a platform jointly developed by FIFA and Lenovo around a proprietary large language model trained on hundreds of millions of historical data points collected from decades of FIFA competitions.

Unlike previous generations of analytical tools, which were generally available only to national teams with substantial financial resources, this platform was provided to all 48 participating national teams, regardless of their budgets or technological infrastructure. Coaches and performance analysts could ask questions in natural language, much like having an ordinary conversation, and receive answers in the form of written reports, data visualizations, tactical simulations, and animated reconstructions of match scenarios rather than simple numerical outputs.

The concept has been championed by Arsène Wenger, FIFA's Chief of Global Football Development, who presented Football AI Pro as a tool designed to democratize access to elite performance analysis by giving smaller football federations capabilities that, until recently, had been available almost exclusively to the world's footballing powers with dedicated data analytics departments.

The tournament also introduced several technologies aimed at improving both refereeing transparency and participant safety. AI-powered body cameras mounted directly on referees' equipment, digitally stabilized through specialized software, broadcast the referee's point of view during all 104 matches. At the same time, separate automated moderation systems monitored social media using AI models trained to recognize patterns of abusive language across multiple languages, enabling them to identify and block hate speech and harassment directed at players.

How a World Cup Team Trains with Artificial Intelligence

Long before the first ball was kicked at this year's tournament, artificial intelligence had already begun influencing nearly every stage of national team preparation: which players are selected, how they train, and even when they should be introduced during a match. Many national team coaches now rely on performance analysis platforms fed by GPS data collected during training sessions, combined with biometric sensors that monitor fatigue and recovery, as well as video systems capable of automatically tagging every technical action across thousands of hours of footage.

The practical result is that a coaching staff which, until recently, depended largely on manually reviewing recordings and subjective observation now has access, every day, to precise quantitative data for every player in the squad: how frequently and intensely a player presses after possession is lost, how effectively they maintain their defensive positioning relative to teammates, or how quickly they recover and return to a normal heart rate between successive sprints.

Injury risk prediction relies on wearable sensors that monitor muscle activation and joint movement, enabling AI systems to recommend individualized training programs tailored to each player's physical condition on a given day. The same models are also used during matches to estimate the optimal moment for making substitutions—an advantage that can prove decisive in the closing minutes of a game.

At the opposite end of the player development pipeline, long before an athlete is ever called up to a national team, other AI models are already analyzing footage from youth tournaments, examining how young footballers move, position themselves on the pitch, and develop physically over time. Their goal is to identify talent patterns that even the most experienced scout could easily miss simply because no human has enough time to watch thousands of hours of obscure youth matches.

All 48 participating national teams had access to the same comprehensive set of analytical data, a fact that neatly captures the broader objective of this transformation: reducing the analytical gap between football federations. According to FIFA's official presentation of the platform, however, Football AI Pro includes one important restriction. To preserve the integrity of tactical decisions made by humans, the system cannot be used during live matches, but only before kickoff and after the final whistle.

The role of the coach is not disappearing. What is changing is the nature of the job: instead of being the person who searches for information, the coach increasingly becomes the person who decides what to do with the information that AI has already placed on the table.

Not Everyone Is Applauding

Making the game more transparent inevitably also means creating a technological infrastructure capable of tracking people, objects, and behaviors with unprecedented precision in a public space.

The scale of this technological deployment has not gone unnoticed by civil liberties organizations. The implementation of such a dense visual monitoring system across 16 stadiums in three different countries has drawn criticism from organizations including the American Civil Liberties Union (ACLU) and Privacy International, both concerned about the precedent set by the widespread use of visual recognition and individual tracking technologies in such a large public environment, even if the systems are officially intended to monitor the game rather than the spectators.

The criticism has not remained purely theoretical. Following Egypt's elimination from the tournament after a VAR-disallowed goal and a penalty appeal rejected during its match against Argentina, Egypt head coach Hossam Hassan stated bluntly: "I saw no respect or fair play," while the Egyptian Football Association subsequently filed an official complaint with FIFA. Canadian coach Alan Koch expressed a similar concern in an interview with CBC, warning that FIFA risks "shooting itself in the foot" through the way it manages these technological controversies. FIFA Referees Committee chairman Pierluigi Collina rejected suggestions that the system favors any particular team, insisting publicly that the objective remains exactly what it has always been: ensuring that matches are decided by what players do on the pitch, not by refereeing mistakes.

Jürgen Klopp voiced a similar position in May 2024, ahead of his final match as Liverpool manager, arguing that the problem is not VAR itself, but the way it is implemented. In his view, technology can reduce human error, but inconsistent application risks generating controversies comparable to those it was originally designed to eliminate.

Club Football Had Already Been Testing These Technologies

In reality, most of these technologies did not suddenly appear with this year's World Cup. They have been tested and refined for years at the club level, in competitions such as the Premier League, the UEFA Champions League, and La Liga. Clubs already rely on specialized platforms developed by companies such as Stats Perform and SciSports for automated scouting across less prominent leagues and competitions, where traditional scouts rarely have the time or resources to travel.

Machine learning algorithms—a branch of artificial intelligence that learns to recognize patterns directly from large volumes of data rather than being explicitly programmed for every situation—simulate thousands of possible versions of the same match before kickoff, helping coaching staffs choose optimal formations and set-piece strategies. At the same time, GPS-enabled training vests worn by players continuously monitor heart rate, distance covered, and sprint intensity, allowing medical teams to identify signs of accumulated fatigue before they develop into muscular injuries.

Greater Precision, Less Emotion

Automation has been introduced precisely where both the question and the answer can be measured and reduced to objective, verifiable data: the position of a player's body at a specific fraction of a second, the speed of a sprint, or the trajectory of the ball. Human judgment, by contrast, has remained where interpretation is still required—determining whether a player in an offside position actually influenced the play, or whether a challenge deserves a yellow or a red card. It is, in essence, a carefully defined division of labor between sensors and people.

Broadly speaking, this is also the direction in which elite football appears to be heading. At UEFA's VAR Symposium, held in Lisbon in January 2025, Portugal head coach Roberto Martínez stated that VAR had already become "an integral part of the game," capable of protecting football by ensuring the correct decisions in critical situations. He added that, once accustomed to the technology, its absence makes the game feel as though an essential tool is missing. At the same time, Martínez emphasized that many situations remain inherently subjective and that the referee must continue to be the ultimate authority on the field.

Speaking at the same event, Roberto Rosetti, the former Italian international referee and UEFA's Managing Director for Refereeing, argued that technology is now "fully integrated into modern refereeing," but stressed that it should be used strictly within the limits defined by the Laws of the Game and should not turn every incident into an endless technical review. In his view, the on-field referee must always retain the final decision.

There is, however, a cost to this level of precision that statistics alone cannot capture: the way AI-assisted officiating changes the emotional experience of watching football. A goal is almost never a completed moment anymore. Increasingly, it is followed by a pause lasting several seconds—or sometimes several minutes—during which the explosive joy of the crowd remains suspended while the virtual review determines whether the goal will stand or be disallowed.

The replay itself, presented through a three-dimensional player avatar, may improve the clarity of the decision, but it also transforms a moment of pure emotion—the roar of the crowd, the embrace of teammates, the collective celebration—into a technical validation process, examined frame by frame before anyone is allowed to celebrate fully. This fragmentation of the game, with repeated stoppages that can sometimes last longer than the attacking move itself, is the inevitable trade-off for greater accuracy: football becomes fairer, but the uninterrupted emotional intensity that has always defined the sport is partially sacrificed. It is therefore no coincidence that many of the criticisms voiced by supporters throughout the tournament were directed not at the accuracy of AI-assisted decisions themselves, but at this imposed pause in the flow of the game, which turns spontaneous celebration into celebration conditional upon a technical verdict.

One of the clearest illustrations of this emotional cost came with Croatia's elimination by Portugal on 2 July 2026, very likely the final World Cup match of Croatian legend Luka Modrić's career. Croatia lost 2–1 after Portugal was awarded a penalty following a VAR review, despite the referee initially judging that no foul had occurred while standing close to the incident. During the second half, three additional Croatian goals were ruled out for offside. The most controversial moment came in the 103rd minute, when Joško Gvardiol appeared to score the equalizer, only for the goal to be disallowed as well.

After the final whistle, Modrić did not hide his frustration, saying of the refereeing decisions: "This makes me angry, and it always goes against us." The following day, the Croatian Football Federation (HNS) submitted an official letter to FIFA explicitly challenging both the application of VAR and the reliability of the ball's sensor technology during the decisive incidents of a match that could have brought Modrić's World Cup career to a very different conclusion.

Football has been accompanied by refereeing controversies since its earliest days. Disputed decisions, goals allowed or disallowed, and refereeing mistakes have always been part of the sport's history. The controversies did not begin with VAR. Technology has not eliminated this tension; it has merely shifted it from the realm of human error to the boundaries between objective measurement and subjective interpretation.

The 2026 FIFA World Cup appears to have demonstrated that football can absorb a substantial amount of artificial intelligence without completely losing its character as a game ultimately officiated by humans. Yet the precise point at which this balance ceases to be acceptable for fans, players, and officials alike remains far from fully tested. Technological progress will continue to push toward automating decisions that today still belong to the domain of human judgment.