LONDON -- The cameras are in place in the English Premier League's 20 stadiums and goal-line technology is ready to be used in a domestic league for the first time in world football.
Most Premier League referees, though, will only get to test the "Goal Decision System" for the first time just days before the season starts next week.
And the set-piece unveiling of Hawk-Eye's camera-based system inside the Emirates Stadium on Thursday saw Arsenal manager Arsene Wenger highlight concerns about how it will cope with complex situations.
"Honestly it's a bit more sophisticated and complicated than you would imagine," Wenger said. "It's not as easy as it looks."
Standing in the goalmouth, Wenger challenged referee Anthony Taylor on the precise application of Hawk-Eye to rule on disputed goals.
"Football can be so quick that the ball can go in and go out and something can happen in the moment between the ball going in and the signal comes up, so what does the referee decide?" Wenger asked.
Taylor sought to reassure Wenger.
"We have a training day on Monday where we are going to spend the whole day with the referees and all the assistants going through the system and exactly work through small anomalies like that," Taylor said. "What if there are two decisions very close?"
Wenger, who has championed technology for years, responded with a more precise scenario.
"The ball goes in, goes out and somebody makes a foul, and the guy wants to kick it in again," he said. "The referee decides in that fraction of a second to give a foul for the defender. And then suddenly it appears to be a goal and he's already decided it's a foul for the defender."
There isn't a precise answer yet.
"While it's probably going to be a small number of incidents like this, it's important we are prepared for these situations and this is what our session on Monday is going to be all about," Taylor said.
Despite his challenging manner under the glare of the cameras, Wenger was keen to underscore his delight that technology has arrived in football to bring "justice" to the decision-making. And he's hoping that the cameras could one day be used to rule on more than just goal-line decisions.
The Premier League's attempts to introduce technology were rebuffed for years by FIFA until President Sepp Blatter reversed his opposition after England midfielder Frank Lampard was denied an obvious goal at the 2010 World Cup.
FIFA is deploying GoalControl-4D, a similar system, at the World Cup in Brazil next year after it was tested at the Confederations Cup recently.