Video refereeing: Watch this penalty decision and vote on whether the system works

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The Under-20 World Cup in South Korea is the latest tournament to trial video assistant referees (Var) - and it has seen a number of controversial decisions.

Football's rule-makers want video referees in place as soon as possible and Fifa president Gianni Infantino wants the system ready for the 2018 World Cup.

But is it conclusive? Does it actually work?