SUBSTITUTIONSpublished at 69 mins
Liverpool 2-0 Cardiff
A raft of changes made by each side after that goal.
On-loan Manchester City player Tommy Doyle is one of those entering the action for Cardiff.
Championship side Bournemouth knocked out by non-league Boreham Wood
National League side will travel to Everton in fifth round
FT: Forest 4-1 Leicester -
FT: Liverpool 3-1 Cardiff
Phil Dawkes
Liverpool 2-0 Cardiff
A raft of changes made by each side after that goal.
On-loan Manchester City player Tommy Doyle is one of those entering the action for Cardiff.
Liverpool 2-0 Cardiff
Pat Nevin
Former Scotland winger on BBC Radio 5 Live
That is the last place you go for a nutmeg if you a Cardiff player. Just kick it out. It has killed the game for them.
Takumi Minamino
All over?
Cardiff get in a real mess at the back, Perry Ng fails to clear and is picked off by debutant Luis Diaz.
The Colombian shows lovely footwork to keep the ball in play, sending it into the danger area and Takumi Minamino is on hand to thrash the ball into the net.
Liverpool 1-0 Cardiff
Careful Will Vaulks, careful.
The Cardiff man wants a corner and then screams in the face of the lineman and referee Andy Madley comes striding across.
"You're on a yellow," he says.
Liverpool 1-0 Cardiff
Caoimhin Kelleher off his line again but makes a better judgement this time, heading away as Jordan Hugill was chasing.
#bbcfootball
Matt: Guarantee that if both incidents were whilst Liverpool were attacking they would have had a penalty in the first half and that would have been a red card.
portmanlovesme: So let's get this right... you can fly off your line, studs, front on, miss the ball and take the player, stop an attack and allow your defence to get back into shape. And all you get is a yellow. Got it.
Liverpool 1-0 Cardiff
Harvey Elliott doesn't look like he has been away.
The former Fulham player shifts the ball onto his left peg before firing wide from outside the area.
Liverpool 1-0 Cardiff
Changes for Cardiff too.
Mark Harris and James Collins make way for Isaak Davies and Jordan Hugill.
Liverpool 1-0 Cardiff
How has he not made it two??
A gilt-edged opportunity for Diogo Jota to double his and Liverpool's tally but he sends a free volley wide from eight yards out.
Liverpool 1-0 Cardiff
Dafydd Pritchard
BBC Sport Wales at Anfield
Perhaps the biggest cheer of the day from Liverpool's fans has been reserved for that double substitution.
Not only is this a debut for new signing Luis Diaz but Harvey Elliott comes on for his first appearance since suffering that awful injury in September.
A huge ovation for both players.
Liverpool 1-0 Cardiff
Double change for Liverpool.
Teenager Harvey Elliott, that's Elliott, gets a standing ovation as he returns to action after a horrible ankle injury.
Colombian Luis Diaz also gets a debut off the bench.
Curtis Jones and Naby Keita make way.
Liverpool 1-0 Cardiff
Nearly a quick-fire double for Liverpool.
Roberto Firmino meets Kostas Tsimkas' cross with a header of his own, but he is no Diogo Jota with his bonce and it ends up being a weaker effort into the hands of Dillon Phillips.
Liverpool 1-0 Cardiff
Pat Nevin
Former Scotland winger on BBC Radio 5 Live
Diogo Jota is not the tallest in the world but he has a fantastic header. That is a stunning header into the far corner.
Diogo Jota
Breakthrough!
How good is Diogo Jota at heading a football? One of the best in the division.
Trent Alexander-Arnold puts in a free-kick towards the penalty spot, Jota has plenty to do but times his leap, arches his neck and sends in a super finish into the far corner.
Brilliant from the Portuguese.
Liverpool 0-0 Cardiff
Cardiff's Will Vaulks into the book for a tug on a red shirt.
#bbcfootball
Steve Stone's Mullett: Maybe i'm cynical, but if that was a Cardiff foul on a Liverpool player, it's a red card.
Mark Willis: As a Liverpool fan, believe this is our worst performance in years. Game not over yet of course...
Liverpool 0-0 Cardiff
Liverpool have a corner which is worked to Curtis Jones around 30 yards out, but it is a wild hit from the Liverpool midfielder, sending his shot into the Kop.
Liverpool 0-0 Cardiff
Caoimhin Kelleher raked his studs down the back of Mark Harris' leg but they felt it wasn't enough for a red card.
Play goes on.
Liverpool 0-0 Cardiff
It's being looked at by VAR.
The challenge is a nasty one from Caoimhin Kelleher, catching Mark Harris on his leg with his studs.
But the officials decide a yellow card will suffice.
Liverpool 0-0 Cardiff
Pat Nevin
Former Scotland winger on BBC Radio 5 Live
I think there is one player with him. In days gone past that would have been a sending off. There is a question to be asked there.
Kelleher made a rotten decision there, don't come out.