Xherdan Shaqiri makes way for Alex Oxlade-Chamberlain.

Can he help Liverpool wrap this up?

Watford are still very much in this.

Alex Oxlade-Chamberlain is getting ready to come on as Jurgen Klopp looks for the comfort of a two-goal cushion.

James Milner unleashes a shot from range, but it's nowhere near the target.

End to end stuff at Anfield!

Liverpool clear on the edge of their own box, Christian Kabasele looks like he's produced a great tackle to halt the hosts' progress but then attempts a needless turn that hands possession back to Liverpool's front-three.

A knock over the top sees Ben Foster come charging out to head the ball away from Mo Salah, though Salah appeared to be offside anyway.

Great stuff.

Aashish: Gritty Watford could be 4-1 up, Liverpool need that second asap.

Wayne Ellis: Can definitely see why Watford are at the foot of the table with finishing like this

Two great chances for Liverpool in the space of a minute, but they can't take either!

First, Mo Salah charges through on goal but knocks the ball to far ahead, allowing Ben Foster to clear.

Then, Roberto Firmino is unable to punish Watford under pressure.

Watford are looking stretched for the first time today.

The ball falls kindly for Roberto Firmino following a sliding tackle by Christian Kabasele in the centre of the pitch.

The Reds forward chooses not to use his team-mates as he eventually fires a low shot at Ben Fosters goal that is collected easily enough by the Watford keeper.

Ismaila Sarr, who has not had his greatest afternoon in front of goal, tries to take on Virgil van Dijk but the Liverpool centre-back nudges his opponent off the ball to clear.

No hint of a penalty according to referee Andre Marriner.

Emma Sanders
BBC Sport at Anfield

Liverpool back to a more recognisable back four with Andy Robertson at left-back. It means versatile veteran James Milner moves up into midfield.

And that will be that for Georginio Wijnaldum, who walks slowly off the pitch.

He could be a potential doubt for Liverpool's upcoming Club World Cup duties.

Andrew Robertson is on in his place.

Everyone's agreed on that one too then...

Nigel Pearson will sense a real chance for his side to get an unexpected result here.

Watford have upped it since Liverpool's disallowed goal and haven't let the hosts settle.

A potential concern for the Reds too is Georginio Wijnaldum, who is currently down receiving treatment.

Ar Vind: Liverpool seem a bit complacent in defence. Gomez is a bit rusty. They need to tighten up.

Jack Lovatt: Unfortunate VAR and very tight, but correct call based on the letter of the law I guess!

Great stop by Alisson, as Gerard Deulofeu almost rubs salt into the wounds following that VAR call.

The Spaniard sprints through on goal, but the Liverpool keeper is equal to the shot as Watford pass up another golden opportunity.

Can Watford make the most of that?

It was a brilliantly worked goal by a Liverpool side not quite at it so far today.

Hope for the Hornets still.

Emma Sanders
BBC Sport at Anfield

VAR strikes again. Just like Roberto Firmino's offside goal against Aston Villa, where it was his 'armpit' that was over the line, it's the same scenario with Sadio Mane.

NO GOAL!

VAR has disallowed the goal with Mane judged to have strayed ever so slightly offside.

The tightest of margins!

Image source, Reuters

Watford build up patiently, and work the ball to Ismaila Sarr, who closes in on goal near enough to get away a shot at goal which Alisson smothers.

Liverpool counter as they did for their opener, and they have a corner for their efforts.

Trent Alexander-Arnold delivers an awkward ball across the face of goal and Adrian Mariappa isn't sure how to deal with it.

He resorts to putting it out for a corner, and the gamble pays off as Watford clear easily.

No changes to report at the break.

We're back under way!