Did you watch the NFL playoff games this past weekend? There was one blown call at the end of the 4th quarter that absolutely cost the Saints the game against the Rams, and the whole world saw it, except for the seven refs on the field. It was so bad to have this happen in such an important situation that the Super Bowl becomes somewhat meaningless this year, and the NFL has egg on their collective faces for not using the very available video tape replay to right the wrong.
In the other playoff game a ticky tacky foul that should never have been called handed a Kansas City Chiefs victory to the New England Patriots. It was the type of foul that could be called many times during the course of a game but rarely is. Usually a warning to the offending player suffices, but not this time with the game on the line. Strange days in the NFL!
In other words, shit happens and life isn't fair! This has been proven over and over again.
In past world cup soccer, there were goals allowed/disallowed that had clear penalties or even the ball crossing the line and then coming out and not seen by the referees on the field. It was getting to be a giant black eye to FIFA.
So they responded in a revolutionary way by creating a VAR - video assist referee. Where a 5th referee, who is on communication with the head ref, is in a booth and plugged into the entire multi angle/cam broadcast of the game with the power to replay anytime they want.
What happened changed the outcome of many games but left an honest and more pure form of the sport. Penalties were taken away or awarded when the ref may have not been in position to make the correct call. Also players conduct when the refs back was turned was policed and their behavior was stellar compared to past tournaments.
Another factor was that the sport and challenges to calls were more streamlined in that the VAR could make decisions on the fly and consult with the head Ref while the game is being played, or during a referee time out and with a small screen on the sideline. Everything was happening in real time.
NFL will no doubt switch to this method eventually. As should all sports.