Video technology will help referees correct "match-changing" decisions including goals, penalty calls and direct red cards at the FIFA Club World Cup which begins on Thursday.
It is the first time that video assistance will be available to referees in a FIFA competition, though the on-field official will retain the first and final call.
Video assistant referees (VARs) will watch live broadcast feeds inside a control room and be able to communicate directly with the referee to help correct "clear mistakes in match-changing situations", FIFA has announced.
Referees will be able to review footage on a pitchside monitor for certain decisions.
The technology was trialled during recent international friendlies involving Italy, Germany and France.
"This represents a big step forward in terms of testing the technology," Marco van Basten, FIFA’s Chief Officer Technical Development told the official FIFA website.
"We feel well prepared after setting everything up with the support of The IFAB, the host broadcaster Dentsu/NTV and Hawk-Eye – one of a number of providers that offer such technology. 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."
Other competition organisers are expected to begin conducting live trials using VARs from 2017 including in Germany, Italy and France.
"The VAR system has been developed, just like goal-line technology, to provide additional support for the referee," said Massimo Busacca, FIFA’s Head of Refereeing.
"We want the essential flow of the game to be maintained and, as always, the first and the final decisions lie with the referee. This is our philosophy, and these principles as well as the practical application of the technology have been explained and demonstrated to our match officials as part of an ongoing training programme."
Kashima Antlers face Auckland City in Yokohama on Thursday to kick-off the FIFA Club World Cup.
