With the Champions League returning on Tuesday, UEFA have restated their December 2018 decision to use Video Assistant Referees (VAR) in the round of 16 this season.
The federation also saw it necessary to publish a VAR guide for fans and clubs.
UEFA VAR guide:
• “The VAR team will constantly check for clear and obvious errors related to the following four match-changing situations:
b. Incidents in the penalty area
c. Red cards
d. Mistaken identity
• The VAR team will check all match-changing situations, but will only intervene for clear and obvious mistakes. The referee can hold up play while a decision is being reviewed.
• If the VAR review provides clear evidence for a serious mistake in one of the game-changing situations, the VAR can then ask the referee to conduct an on-field review (by viewing replay footage in the review area). The final decision can only be taken by the referee.
• The VAR is also able to take into account any infringement that could have taken place in the immediate build-up to the incident (the attacking phase of play).
• For 'factual' decisions (e.g. offsides, fouls in or outside the penalty area), the VAR can simply inform the referee of those facts and the on-field view screen isn't needed, but it is always the referee who takes the final decision.
• The on-field review process will be communicated within the stadium using either the stadium screens or the public announcement system.
• Because VAR is being used, there will be no additional assistant referees.”