FIFA refereeing bosses celebrated what they described as a scandal-free World Cup for match officials on Friday, saying that the video replay system had helped achieve an accuracy rate of 99.3 percent for decisions in the group stage.
"After 48 games, we haven't had a single scandal, and that's very important," FIFA's director of refereeing, Massimo Busacca, told reporters.
The World Cup in Russia is the first to use Video Assistant Referees (VARs) who monitor the game on television screens and communicate with the pitch official.
The VARs check decisions which could potentially change the outcome of a game and, if they feel the pitch referee has made the wrong call, suggest he review the incident on a pitchside monitor.
Pierluigi Collina, head of FIFA's referee committee, said that 95 per cent of the decisions taken initially by referees had been correct, and this had been raised to 99.3 percent thanks to the intervention of VAR.
"We would have preferred to speak of 100 per cent but 99.3 per cent is something that is very, very close to perfection," said Collina, adding: "VAR doesn't mean perfection, there could still be some wrong interpretation or mistake."
He said that 335 decisions had been checked in the 48 group stage matches and there had been 17 VAR reviews -- 14 on the field and three by the VAR assistants.
However, the Italian former World Cup referee would not comment on individual decisions, such as failure to award Serbia a penalty against Switzerland when Aleksandar Mitrovic appeared to be held down by a defender.
"It is interesting that you are interested in the 0.7 per cent (of wrong decisions) and not the 99.3 percent," he said in answer to one question.
"I think that 99.3 percent (accuracy) is an acceptable figure after these 48 matches."
He said that the average time taken for a VAR decision was 80 seconds.
"The VAR prefers to spend five or 10 seconds more to be very, very sure," he said. "Accuracy is very important even if it costs 10 seconds, the important thing is to achieve the correct result."
The news conference was shown several key incidents in which VAR was used and reporters were able to hear the conversations between the video and on-pitch officials.
These included South Korea's first goal in their 2-0 win over Germany which resulted in the elimination of the world champions.
The goal was initially disallowed for offside but allowed to stand after a VAR review showed that the ball came off a German player before Kim Young-gwon put it in the net.
Collina said the goal could have been awarded without a pitchside review but added: "It was a good idea to make an on-field review to show that the incident had been checked by everyone."
Reuters
