Football history will be made at the FIFA Club World Cup when video replays will be used for the first time by referees during the event in Japan from Dec. 8-18.
The video assistance will be used to support referees with "match-changing" decisions for the first time in a FIFA competition.
"This represents a big step forward in terms of testing the technology," said Marco van Basten, FIFA's chief officer technical development.
"We feel well prepared after setting everything up.... At the same time, it's important to remember that we are entering somewhat unchartered territory here, given that we are going live for the first time.
"Ultimately, these tests should prove invaluable in terms of determining whether the processes are sound or whether any further refinements are needed."
- FIFA.com (@FIFAcom) December 7, 2016
FIFA announced this past summer that competitions in six countries -- including Germany's Bundesliga and United States' Major League Soccer -- had been approved to run experiments with video assistant referees (VARs).
The off-line experiments did not involve referees and FIFA is using the live trial for the first time at this Club World Cup in Japan.
FIFA president Gianni Infantino said he hopes VARs will be used to support refs at the 2018 World Cup in Russia.