Football and technology

Football was for most of its history one of the least technology-dependent major sports. The Laws of the Game were designed to be playable anywhere, on any surface, with the same basic equipment. Decisions on the field were taken by a referee with two assistants, with no recourse beyond what they had seen. Coaches' tactical analysis was based on what they could remember from watching matches in person. Broadcasting was straightforward video coverage with little additional information overlaid.

That changed substantially from the early 2010s onwards. Goal-line technology, video assistant referees and semi-automated offside were adopted at the elite level. Data analysis became a major part of how teams scout, train and prepare. Broadcasting was transformed by on-screen graphics, replay analysis and statistics. None of these changed the basic shape of the game, but the experience of playing, coaching, officiating and watching modern football became substantially different from the football of a generation earlier.

Goal-line technology is a system of cameras or sensors that detects whether the whole of the ball has crossed the goal line. It produces a yes-or-no answer within a second of the ball crossing the line, transmitted to the match referee's watch. The technology was developed across the 2000s and 2010s, with several different systems competing for adoption. IFAB approved goal-line technology for use in matches in 2012, and FIFA used it for the first time at the 2014 World Cup in Brazil.

Goal-line technology was adopted to settle a recurring problem. Disputed goal-line incidents, where it was not clear whether the ball had crossed the line, had affected major matches across the previous decades — including a Frank Lampard shot for England against Germany at the 2010 World Cup that was a clear goal not given. With the technology in place, those incidents became much rarer in competitions using the system. The Premier League, the Bundesliga, Serie A, the Champions League and many other leading competitions adopted goal-line technology across the 2013-15 period.

The video assistant referee is an official based in a video room who reviews specific match decisions using television replays. VAR can be used to review four categories of decision — whether a goal should stand, whether a penalty should be awarded, whether a direct red card should be given, and cases of mistaken identity in a disciplinary incident. VAR cannot review every decision in a match — only those four categories — and the on-field referee remains the final authority. The system was added to the Laws of the Game in 2018 after several years of trials.

VAR was used at the 2018 World Cup, the first men's World Cup at which the system was used. Most major European leagues adopted it across the 2018-2020 period. The reception was mixed. VAR corrected many obvious mistakes, but its use also extended the time taken on decisions, occasionally to the point of breaking the flow of the match. The exact protocols — when VAR should intervene, how much time it should take, what counts as a "clear and obvious" error — were refined after adoption and remained debated.

Semi-automated offside technology uses tracking cameras and ball data to produce an offside alert for video match officials, who then check the decision before it is communicated to the referee. The system was introduced at the 2022 World Cup in Qatar, where it was credited with speeding up offside reviews compared with the manual VAR offside checks used at the 2018 tournament. The Champions League and several major European leagues adopted the system in later seasons.

Other connected technologies followed. The ball used at the 2022 World Cup contained a sensor that recorded the exact moment of contact, helping referees decide on close handball and offside calls. Camera-based player tracking became standard at the elite level for both officiating and analysis. The general trend was towards more decisions being checked faster, with less reliance on human-paced video review.

GPS trackers worn by players in training, sometimes also in matches, produce data on running distance, sprint speed, acceleration and recovery. Event-level match data, recording every pass, shot, tackle and other action, is gathered by specialist data providers and used by clubs for scouting and tactical analysis. Video analysis tools allow coaches to break down opposition matches in detail. Most professional clubs at the elite level developed dedicated analytics departments alongside their coaching staff.

Concepts like expected goals (xG), pressing intensity, and various positional metrics have entered the wider football conversation through this data work. The information became used in broadcasting graphics, in football journalism, and increasingly in conversations between supporters as well. Data analysis is unlikely to replace traditional scouting and coaching judgement, but it has become a routine part of how the professional game operates, in a way that was not true a generation ago.

Most of the technologies described above became well established at the elite level. Goal-line technology and VAR are used in many major leagues and tournaments. Data analysis is standard at professional clubs. Broadcasting was transformed across the 2000s, 2010s and 2020s. Lower levels of football remain less technology-dependent — most amateur, semi-professional and youth football is still played and officiated without much technology — but the elite professional game moved a long way from where it was a generation earlier.

The debates that remain are mostly about how far to take the trend. Some observers favour more automation, faster reviews and more data; others worry about losing the human element that has been part of football's character since 1863. The basic direction of travel — gradually more technology, applied to specific decisions and analytical tasks, leaving the basic shape of the game intact — became one of the defining features of the modern era. By that point, the era in which technology was a marginal influence on elite football was clearly over.