FIFA president Gianni Infantino has claimed that video replays at the Club World Cup have produced "extremely positive results".
The system was first used on Wednesday to award a penalty in Kashima Antlers' 3-0 win over Atletico Nacional, with the referee alerted by his assistant.
Its introduction, however, has had a mixed reaction from players and coaches at the tournament, including Real Madrid forward Cristiano Ronaldo.
"The results are extremely positive," Infantino told reporters.
"Of course there are learnings, of course there are a few topics that we have to look into and discuss in more detail, but the result is extremely positive.
"Why? Because the referee has been able to take the right decision and justice and transparency have been brought to the game."
Video assistant referees have assisted officials during two international friendlies this year, but the Club World Cup represents their first use in FIFA competition.
Giuseppe Labellarte
