That is the age-old World Cup question for Germany, who crashed out as Japan beat Spain thanks to an opinion-dividing winner that left many scratching their heads.
Kaoru Mitoma’s cutback for Ao Tanaka’s tap-in happened just after the ball looked to have crossed the bye-line.
Even after cropping and zooming it looked incredibly close. Eventually it was ruled that the ball had not fully crossed the line.
In other words, if you drew an imaginary line upwards at 90 degrees from the far edge of the whitewash, it would have still passed through the curve of the ball - albeit only just - even though the part of the ball that touched the ground had fully crossed the line.
The goal was initially ruled out by the assistant referee after a long pause, then the video assistant referee (VAR) intervened and ultimately Japan’s lead would stand - and they would go on to win. (BBC Sport)