How Does VAR Work? What Is Semi-Automated Offside?
Hardly a day of the 2026 World Cup passes without a VAR story: disallowed goals, stoppage-time reversals, reviews announced to the whole stadium. Knowing when the system is allowed to intervene makes the decisions much easier to follow.
Below we explain VAR's scope, semi-automated offside technology and the referee announcements, all in Q&A form.
01 Which situations can VAR review?
VAR can only intervene in four types of decision: incidents leading to a goal (offside, foul, handball), penalty decisions, direct red cards and cases of mistaken identity. Anything else — second yellow cards, corners or throw-ins — is outside VAR's scope.
02 Can VAR overturn the referee's decision?
VAR itself decides nothing; it alerts the referee only when it sees a 'clear and obvious error'. The final call always belongs to the on-field referee, who either reviews the incident on the pitchside monitor or, for factual calls like offside, applies VAR's measurement directly.
03 How does semi-automated offside technology work?
Dedicated cameras under the stadium roof track a large number of points on every player's body dozens of times per second, while a sensor inside the ball records the exact moment it is kicked. The system combines both data streams to generate the offside line automatically and alerts the VAR room within seconds.
04 Is there really a sensor inside the ball?
Yes. The match ball carries a motion sensor at its centre sending data hundreds of times per second. Because it pinpoints the moment of contact to the millisecond, it is also used to determine whether a touch occurred in disputed situations — such as who last played the ball before it reached a player in an offside position.
05 Why do referees announce decisions to the stadium?
After a VAR review, the referee announces the decision and a brief reason over the stadium PA and the broadcast feed. The goal is transparency: fans hear directly from the referee which incident was reviewed and why the call was made.
06 How much does a VAR review extend a match?
Every review is logged as lost time by the fourth official and added to stoppage time. That is why added periods beyond 10 minutes have been common in 2026 — and by rule, any attack that could produce a goal is allowed to finish before the whistle.