Soccer's rule-makers on Saturday approved in-game trials with video assistance for referees as Gianni Infantino used the start of his FIFA presidency to push innovation in the sport.
Tests initially will be in private before moving to a live pilot phase with replay assistance by the 2017-18 season at the latest, the International Football Association Board's annual meeting decided.
IFAB will have to approve all trials, with 13 leagues or associations already expressing an interest in hosting tests.
It's four years since IFAB first sanctioned technology in soccer after being held up for years by Infantino's predecessor Sepp Blatter but that was restricted to determining whether the ball crossed the line. And Infantino is keen to show that FIFA has embraced a "new era" with the reign of Blatter now over.
"We have taken really a historic decision for football," Infantino said in the Welsh capital Cardiff. "FIFA and IFAB are now leading the debate and not stopping the debate. We have shown we are listening to the fans, the players and to football."
IFAB rejected allowing coaches to have appeals where videos of incidents could be examined. The use of video will be restricted to referees ruling whether a goal has been scored, a penalty should be awarded and a player should be sent off or in cases of mistaken identity. A large multi-camera operation will be required for games where video assistance is used rather than just three cameras.
"Everybody believes they have been talking too long and we can only have a meaningful decision once we see what impact it has on the game," said David Elleray, chairman of the English Football Association refereeing committee.
"Does it bring more benefits or more problems? This isn't going to solve all the controversies because no matter how many words we have, human beings have to make subjective decisions."
The experiment is set to see a video assistant referee given access to replay monitors and will review actions on the request of the referee or by proactively alerting referees to uncertain incidents.
"In an ideal world the referee would ideally see the footage directly and clearly in a few years' time the technology would be available but at this moment in time, the referee may have to run to the halfway line to see something on an iPad," said Football Association of Wales chief executive Jonathan Ford, who hosted the meeting.
FIFA controls half of the eight votes on IFAB, which also features the four British federations. A motion requires at least six votes to be approved.
Among other decisions by IFAB, experiments with a fourth substitution will be allowed in extra time within a competition or league that's yet to be determined.
IFAB also approved a complete revision of the laws of soccer to "address anomalies and inconsistencies."