ExplainedFA Cup key information: Replays, VAR, substitutions and more
The Reds' third-round tie with their League One opposition at Anfield kicks off at 2pm GMT.
Will there be replays?
Replays have been removed for the third and fourth round this season.
The FA said: "This exceptional decision was approved by the FA Board on Friday 17 December and has been taken in the wider interest of English football to alleviate the possibility of fixture congestion following several postponements in recent days and continued uncertainty ahead due to COVID-19.
"Replays will return up to and including the fourth round of the Emirates FA Cup from the 2022-23 season onwards."
What happens if scores are level after 90 minutes?
Third and fourth-round ties will be settled on the day, using extra-time and a penalty shootout if required.
Is VAR in use?
In the third round, VAR will be in operation for ties hosted at Premier League stadiums.
In the rule book for this season's competition, it states: "The Association reserves the right to select any match in the Competition Proper, at its absolute discretion, in which VARs will be used."
How many substitutes can be used?
Teams are able to name nine substitutes and field five of them throughout the game.
Should a player suffer a suspected concussion, a club is permitted to make an additional change.
When is the fourth-round draw?
The draw for round four is set to take place on Sunday at 4.50pm GMT. It will be broadcast live on ITV in the UK.
FA Cup scheduled dates
Fourth round: Saturday February 5
Fifth round: Wednesday March 2
Quarter-final: Saturday March 19
Semi-final: Saturday April 16
Final: Saturday May 14
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