The Reds remain unbeaten in the top flight after 16 matches and head into this high-profile match sitting top of the division, whereas 20-time champions United are down in sixth place.
Not since March 1990 have Liverpool had a bigger points margin heading into a top-flight match against their arch-rivals, with the gap currently standing at 16 points as a result of the sides' contrasting starts to the season.
Liverpool have dropped points in just three games this term and are now the last unbeaten side standing following defeats for past two champions Chelsea and Manchester City over the past three weeks.
With Man City falling to a 2-0 reverse at Stamford Bridge last time out, the Reds stand a point clear at the summit. The task for Jurgen Klopp's men is to now live with the pressure that comes with being the best in the country, with another five months to see out.
This is not exactly new territory for the Merseyside outfit, having mounted a few notable title challenges in the recent past, but the group of players put together by Klopp certainly seems to be made of far sterner stuff - from summer signing Alisson Becker in goal through to arguably the division's most talented player in Mohamed Salah up top.
Strengthening at the back with the addition of Alisson during the off-season, six months after bringing in club-record signing Virgil van Dijk from Southampton, has more than paid off for Liverpool. Just six Prem goals have been shipped all season, leaving them on course to break the record set by Chelsea in 2004-05.
In fact, the Reds have not conceded more than one goal in a game in any of their last 19 league outings - their best run of defensive form since the late 1970s - and they continue to score goals at an impressive rate at the other end of the pitch.
Salah has made a mockery of those who suggested that his 2017-18 goalscoring return would be a one-off, racking up 10 goals already this time around to joint-lead the scoring charts. The Egyptian has opened the scoring in seven matches, meanwhile, and scored the winner six times - both league-high tallies.
However, Liverpool's famed front three of Salah, Roberto Firmino and Sadio Mane - which has been broken apart at times this season with Klopp using a 4-2-3-1, depending on the opponents - have failed to score or assist a goal in a Premier League game against United in nearly 1,000 combined minutes on the field.
All three men played in a part in last weekend's 4-0 destruction of Bournemouth, which was arguably the first time that Klopp's men have truly swept aside a team since cruising to a 3-0 win over Southampton at the end of September.
That was followed up by a tense 1-0 win over Napoli in the Champions League in midweek, keeping the Reds on course for silverware on multiple fronts as they embark on a tough run of games that sees them face United, Arsenal and Man City in the next three weeks.
Come through that run unscathed and supporters really can begin to believe that this will finally be their year.
Recent form in Premier League: DWWWWW
Recent form (all competitions): WLWWWW
While Liverpool fans have plenty to be excited about, it is a different matter entirely for those of a Man United persuasion. One win from their last five league matches shows just how far the mighty have fallen.
The Red Devils did at least manage to end their four-game winless run last weekend with a straightforward 4-1 triumph over Fulham, though it was a case of one step forward and two steps back due to their performance against Valencia in midweek.
A 2-1 loss at the Mestalla would prove costly for United as it denied them top spot in their group, meaning a difficult last-16 tie in the Champions League when European action resumes two months from now.
Even accounting for the win against Fulham, Jose Mourinho's underperforming side have taken only six points from the last 15 on offer. A defeat to neighbours Man City was followed up by successive draws with Crystal Palace, Southampton and then Arsenal.
Momentum just seems impossible to come by at the moment for the country's most successful side, last winning back-to-back matches at the beginning of November.
United's scoring stats are down on last season, their defensive stats are down on last season and, as a result, their points tally is substantially down on last season. This time 12 months ago, the Red Devils had nine points more and were only kept off top spot by the blistering form of runaway champions Man City.
Mourinho may have repeatedly claimed that his side overperformed in finishing second last time out, but there can be no excuses about their constant below-par showings this term, most recently in the defeat to Valencia when simply failing to turn up.
Their 26 goals against in the Premier League is just two fewer than the total they conceded throughout the whole of 2017-18, with just two clean sheets being kept - incredibly, only five other sides have a worse defensive record.
Mourinho can at least fall back on a decent record at Anfield, winning on half of his eight visits there in the Premier League to give him the best win percentage among managers with 5+ such games in the competition.
It was 1990 the last time United were this far behind Liverpool at Christmas. Victory on Sunday will close the margin slightly, but even then there will be lingering doubts over whether Mourinho is the man to bring the glory days back to Old Trafford.
Recent form in Premier League: WLDDDW
Recent form (all competitions): DWDDWL
Ahead of a run of five games in 18 days for the Reds, injuries appear to have hit hard. Joel Matip has joined fellow centre-back Joe Gomez in the treatment room after fracturing his collarbone against Napoli, leaving just Dejan Lovren to partner Van Dijk.
Not ideal for the busiest period of the campaign, with Trent Alexander-Arnold also ruled out of the festive fixtures and James Milner requiring a late fitness test. Should the Englishman be declared fit, he will likely slot in at right-back for the second league game running.
In terms of the visiting side, Mourinho rotated his squad for the trip to Valencia, even if that did ultimately come back to haunt him with top spot in Group H there for the taking.
Romelu Lukaku is looking a shadow of the player United signed 18 months ago, but injuries to Alexis Sanchez and Anthony Martial may leave Mourinho with little choice but to use the Belgian for a second match running.
Liverpool possible starting lineup:
Alisson; Milner, Lovren, Van Dijk, Robertson; Wijnaldum, Fabinho, Keita; Salah, Firmino, Mane
Manchester United possible starting lineup:
De Gea; Young, Bailly, Jones, Shaw; Herrera, Fellaini, Matic; Lingard, Lukaku, Rashford
Head To Head
Sunday's meeting will be the 201st between Liverpool and Man United in all competitions, with the Reds winning 65 of those and suffering 80 defeats.
The Red Devils are aiming to win back-to-back league matches against their rivals for the first time since January 2016 when winning four in a row.
Liverpool have failed to win any of their last eight Premier League games against United overall - they have not gone longer without a win since April 1988 (12 games).
The last two encounters at Anfield have finished level - only once previously have these sides drawn three consecutive games in all competitions on Merseyside (January 1921).
We say: Liverpool 2-1 Manchester United
Liverpool have won four matches in a row and six of their last seven in all competitions, while also boasting their joint-longest unbeaten run of form in the top flight since 1990. United, by comparison, are 16 points off the pace and head into this match on the back of another setback in midweek. Recent results point to only one outcome, although the form book so often goes out of the window for derbies such as this.