Mo Salah was once again the hero for those in red, scoring two stunning goals as his individual brilliance made the difference on a scrappy afternoon of football.
Surprisingly, this was one of the trickiest matches Liverpool has faced this season and Watford, rock-bottom of the league, will be bitterly disappointed to have not come away with at least a point.
The script for Liverpool games this season, in particular at Anfield, has remained largely the same; dominate possession early before inevitably running rampant.
On paper, separated by 20 places and 37 points, this was the biggest mismatch of the Premier League season so far.
Watford, a team with just one win to its name and already six points adrift of safety, against a ruthless Liverpool side that was unbeaten in a club record 33 matches.
The Reds had taken a staggering 73 points from the last 75 available, winning 24 and drawing one of its previous 25 matches.
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Though the team started surprisingly well, the omens did not look good for Watford on this part of Merseyside.
In the last three seasons, the Hornets have lost each match at Anfield by five goals -- 5-0, 5-0 and 6-1 -- with the club's last win coming 20 years ago.
But the elements, even if not the Watford front line, were giving Liverpool's defense some problems.
It was a blustery afternoon in the northeast and the wind was whipping through the stadium, causing stand-in central defender Joe Gomez to misjudge the flight of the ball on more than one occasion.
The sizable attacking figures of Troy Deeney and Abdoulaye Doucoure were not making life any easier.
Perhaps it was those conditions -- indeed, manager Jurgen Klopp has history of blaming the wind for bad results -- that were not allowing Liverpool to play its usual fluid brand of football, and Watford was doing a good job of making the game a scrappy, bitty affair.
In fact, as the game approached half time it was Watford which had created arguably the best chance of the match.
Ismaila Sarr's fantastic low cross from the right evaded the outstretched boot of Deeney by a matter of millimeters, with goalkeeper Alisson a helpless bystander.
The yellow and black wave then carved Liverpool open down the right again, as Sarr's cutback found Doucoure totally unmarked in the area but the midfielder somehow contrived to miss the ball completely.
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It was a miss that Watford would be ruing just a minute later, as Gerard Deulofeu's scuffed corner resulted in a blistering Liverpool counterattack that Salah finished in stunning fashion.
The time between Deulofeu's miskick and Salah's goal was just 15 seconds, highlighting the devastating effect Liverpool's front three can have on opposition defenses.
But this Liverpool back line has been looking a lot creakier than it did last season and once again Watford had a glorious opportunity to get on the scoresheet.
Deulofeu's fantastic run and cross found its way to Sarr at the far post and, with the freedom of Liverpool, the Senegalese forward awkwardly miscued his shot, which embarrassingly ended up going behind him.
Those two misses meant that Liverpool somehow went in ahead at half time and, though his team was not playing well, Klopp will have been more than satisfied.
One quality that Liverpool sides over the years have lacked is the ability to eke out narrow or scrappy results when not playing at their best, one of many factors that has seen the club go almost 20 years without a top division title.
This Liverpool team, however, feels different and the German coach has instilled an unerring belief into his players that they can get a result under any circumstances.
The home side thought it had extended its lead just minutes into the second half through Sadio Mane's thumping header, but VAR ruled that the forward's hip had strayed fractionally offside.
From then on, the tension around the ground became palpable as Watford once again had a brilliant chance to level the scores.
Unsurprisingly it was Deulofeu at the heart of it, beating Trent Alexander-Arnold in a race but then being denied by the imposing figure of Alisson in the Liverpool goal.
Inside the last 10 minutes the nerves inside really began jangling, not aided by some sloppy play from Liverpool's defenders.
Alexander-Arnold's poor lofted pass put Gomez in trouble, before Virgil van Dijk almost scored a comical own goal; relief was etched on the Dutch defender's face when he saw the ball had merely gone out for a corner.
When Salah finally scored the second, it was met largely with an outpouring of relief from those in the stands, rather than joy.
Without playing well, Liverpool is once again 11 points clear at the top of the Premier League.