Video assistant referee used for first time at FIFA Club World Cup
History was made in Wednesday's Club World Cup semifinal between Atletico Nacional and Kashima Antlers when a touchline video assistant referee (VAR) employed replay technology in an official FIFA match to award a penalty.
The decision came with half an hour gone and the match still goalless when Kashima's Daigo Nishi went to ground after tangling with Atletico defender Orlando Berrio.
Nishi had been standing in an offside position when a long free kick was played into the area but was deemed not to have been interfering with play.
Referee Viktor Kassai -- who did not see the incident -- ran to the touchline where he took approximately 30 seconds to watch a replay of what happened before pointing to the spot.
Shouma Doi converted to put the hosts 1-0 ahead. The Japanese side went on to win 3-0 to become the first Asian side ever to reach the final of the competition. They will face either Spanish giants Real Madrid or Mexico's Club America -- who play in the other semifinal on Thursday -- in Sunday's final.
"This is the first-ever live trial with Video Assistant Referees at a FIFA competition, so this is something that is new for everyone -- especially to see the referee run to the video replay area at the side of the field," said Massimo Busacca, FIFA's Head of Refereeing.
"In the incident tonight, the communication between the referee and the video assistant referee was clear, the technology worked well, and ultimately the final decision was taken by the referee, which will always be the case since the VARs are only there to support."
Last week, it was confirmed that video replays would be used for the first time by referees during the tournament in Japan.
The video assistance will be used to support referees with "match-changing" decisions for the first time in a FIFA competition but with the human official retaining the final say.
"The clear message we've got from players and coaches throughout the world is that they would like the referee on the day to remain the main decision maker and that's why the option is always there to go and look at the footage directly," said David Elleray, Technical Director of The IFAB.
The Club World Cup is the end of the test process for VARs but live trials could go ahead globally in the future.
"Once the official experiments begin, the competition organisers will send a great deal of information to The IFAB, which will be analysed by KU Leuven university," Elleray added.
"We'll be wanting to look at how often video reviews are used and how often a referee confirms or changes a decision based solely on the information from the Video Assistant Referee or after an on-field review.
"More importantly, we will want to examine how the VAR system impacts on the behaviour of players, the behaviour of referees, the response of fans in the stadium and the response of people watching on television. So there will be a great deal of information that we'll need before The IFAB takes a final decision on the implementation of VARs in 2018, or 2019 at the latest."
Dermot Corrigan is a Madrid-based football writer who covers La Liga and the Spain national team for ESPN FC. Follow him on Twitter @dermotmcorrigan