Our referee is Craig Pawson. He will be assisted by Gary Beswick and Richard West. The fourth official is Jonathan Moss and the VAR is Andre Marriner.
Liverpool: Alisson, Alexander-Arnold, Robertson, R. Williams, Fabinho, Thiago, Wijnaldum, Milner, Jones, Salah, Firmino.Subs: Kelleher, Mane, Oxlade-Chamberlain, Minamino, Tsimikas, Shaqiri, Origi, Phillips, N. Williams.
Manchester United: Henderson, Wan-Bissaka, Shaw, Maguire, Lindelof, McTominay, Pogba, Van de Beek, Greenwood, Rashford, Cavani. Subs: De Gea, Telles, Tuanzebe, Fernandes, Fred, James, Mata, Matic, Martial.
Manchester United are further unbeaten here at home in their last seven games against The Reds.
Manchester United go into this game at Old Trafford as favourites and they also have the record of knocking Liverpool out of the FA Cup more times than any other team have managed.
Liverpool have failed to convert golden opportunities into goals in recent times and that is one of the reasons they have slipped down the league table.
Since then Liverpool have lost to Burnley at Anfield and Manchester United narrowly defeated Fulham.
This is the second time in a week that these giants meet. The last game in the league last Sunday ended in a goalless draw.
Welcome to Old Trafford for our live coverage of this FA Cup fourth round encounter between Manchester United and Liverpool
Kick-off! We are underway here in Lancashire.
Liverpool are the first to get a shot in and Wijnaldum receives a through-ball from Salah. The shot hits McTominay instead of the goal.
Manchester United secure the first corner of the game after van de Beek fails to get at the end of Shaw's pass. Liverpool clear the corner.
It has been a good start for McTominay. A few good passes into the midfield from him early on.
Alisson is off his line after Rashford lofts a pass towards Cavani. That nearly bounced over Alisson.
It has been a confident start by the home team early on.
Greenwood is free on the right and combines nicely with Rashford. He decides to shoot but Alisson boots it away.
Greenwood is at it again after Cavani finds him The final shot is well WIDE!
Milner runs down the left for Liverpool but Lindelof does well to send the ball out for a throw to The Reds.
GOAL, LIVERPOOL, SALAH! 0-1: United had a corner on the other end. Liverpool clear and start via a quick Alisson throw. They build slowly and Wijnaldum finds Firmino and offloads to Salah, who SCORES with a loft over Henderson!
That will be the start the Klopp wanted. They have struggled to score goals recently.
Liverpool build again and Jones tries his luck from a distance. This time Henderson moves quickly to take possession.
McTominay fouls Firmino and Liverpool have a promising free-kick. Alexander-Arnold takes it and it flies OVER!
OUCH! Rashford and Thiago clashes in the air but they both seem ok and we continue.
GOAL, MANCHESTER UNITED, GREENWOOD! 1-1: Liverpool were near the United penalty area. United counter-attack and Rashford sends a superb ball to Greenwood, who finishes it off!
NO PENALTY! Van de Beek is down in the Liverpool area after a pass from Rashford. Pawson is not interested.
It has certainly been a better 30 minutes than last weeks encounter at Anfield.
Thiago tries a long-ball to Firmino down the middle but it reaches Henderson first.
United secure a set-piece in a good position after Thiago is penalised. McTominay takes it and Williams sends it OVER for a corner!
Shaw takes the corner and Pogba fires it OVER the cross-bar!
United have another corner. Again Shaw floats it in and this time the header from McTominay rises over the bar.
Rashford is down after a challenge from Thiago but the referee waves his finger and is not interested.
Liverpool now have a corner and Alexander-Arnold floats it in. Thiago sets up Milner but his angle sends the ball well wide.
YELLOW! Fabinho is forced into trouble by Alisson and he is booked as a result following a foul on Cavani. United have a great set-piece! Pogba is all over it and sends it OVER!
United want the lead before the break. Rashford, van de Beek and Shaw combine well but Thiago is there to clear.
HALF-TIME: MANCHESTER UNITED 1-1 LIVERPOOL. After one minute of stoppage time we head into the break all-square at one goal apiece. United have looked really good in the first 45 and Liverpool have struggled a bit defending set-pieces.
Kick-off! We are back underway in the second half. The teams are unchanged.
GOAL, MANCHESTER UNITED, RASHFORD! 2-1: United take the lead two minutes after the break! A mistake by Williams where he fails to intercept the ball sees Rashford into a gap after a lofted pass from Greenwood. Rashford do not make mistakes from there!
Rashford collides with Fabinho but they both seems ok to continue.
United are certainly targeting the side of Rhys Williams. Will we see a Liverpool change soon?
Salah and Firmino combines well near the United penalty area. Not the best finish from Bobby sees a good chance go to waste.
GOAL, LIVERPOOL, SALAH! 2-2: Salah strikes again! Milner makes a dynamic run into the box. He passes it in and Firmino lets it run for Salah, who sweeps it in past Henderson. It started with a poor Cavani pass.
SUBSTITUTION: Liverpool bring on Mane for Wijnaldum.
United are seeing quite a bit of the ball now as they are intent on retaining possession.
Liverpool secure a corner after a sliding tackle by Wan-Bissaka. After some initial Liverpool pressure we have a goal-kick.
SUBSTITUTION: Manchester United make a double change. Bruno Fernandes is on for van de Beek and Fred is on for Greenwood.
A great SAVE by Henderson as he denies Salah a hat-trick!
YELLOW! Mane is booked for a sliding tackle on Fred.
Liverpool come again and great interplay between Alexander-Arnold and Firmino leads to a shot by Thiago. He fails to keep it down.
Liverpool build slowly and Salah tries to catch out Henderson but the keeper has it covered!
GOAL, MANCHESTER UNITED, FERNANDES! 3-2: Cavani milks a foul out of Fabinho in a promising position. Fernandes is all over it and SCORES to Alisson''s left! Great goal!
SUBSTITUTION: Firmino and Thiago have now been replaced by Shaqiri and Origi.
Liverpool secure a corner but United do well to clear it quickly.
Jones does well to get into space down the left and he gets away from Cavani.
SUBSTITUTION: United now make a change and Rashford has been replaced by Martial.
Jones gains ground down the left again and Liverpool despite being behind build patiently. They lose the ball and then Cavani's header hits the post after a Fernandes cross.
We are now into four minutes of time added on for stoppages.
YELLOW! Pogba is booked for a foul on Jones and Liverpool have a promising free-kick. Alexander-Arnold takes it but Salah's final shot is WIDE!
FULL-TIME: MANCHESTER UNITED 3-2 LIVERPOOL. A much better game than the one we had at Anfield and a Fernandes free-kick sends United into the next round. Thank you for joining us.