The English Premier League will test Video Assistant Referees (VAR) technology across multiple games for the first time on Saturday.
After VAR tests at individual fixtures last season, the Premier League now wants to see how the system copes with several games at the same time.
The trial, across all five 3pm kick-offs, will be at the central VAR hub.
There will be no communication with anyone at the grounds at which the games are taking place.
The trial limits the use of VAR to goals, penalty calls, direct red cards and cases of potential mistaken identity.
In April, Premier League clubs voted against introducing VAR for the 2018-19 campaign.
As with last season, it will be used in the EFL Cup and FA Cup, but only at top-flight grounds.
It was in operation at 19 games last term, a number it is thought will rise to about 60 this season.