Liverpool are flying high in the league after demolishing a futile Watford side 5-0 in their last domestic outing leaving them a point behind Chelsea in second place if they come away with a win at Old Trafford.
The Reds are the only unbeaten team left in the league and are currently boasting an impressive run of 21 games without defeat in all competitions.
Liverpool have already played fellow league contenders Chelsea and Man City in that run and perhaps face their toughest challenge against Manchester United away from home this weekend.
The Reds are on their longest unbeaten run under Jurgen Klopp and the longest overall since Roy Evans was in charge back in March 1996.
That unbeaten run includes the exhilarating and electrifying 3-2 win in Madrid against Atletico midweek.
It was a game in which Mo Salah scored in his 9th consecutive game, becoming the first player in the club's history to achieve that feat; another record broken.
Manchester United find themselves embroiled in a different situation: talks of Ole Gunnar Solskjaer continuing at the Red Devil's helm is in question once more after a series of underwhelming results domestically.
The arrival of Cristiano Ronaldo gave the Manchester giants a necessitated lift. CR7 has been instrumental in rescuing the Red Devils on several occasions.
The Portuguese superstar is perhaps past his peak, but on his day he is as deadly as any man on the planet with the ball at his feet (or in the air!).
Ronaldo showed his evident quality in Wednesday nights dramatic win over Atalanta where his team found themselves 2-0 down at half time, before an inspired comeback saw them beat the 6th placed Serie A team 3-2.
Although the result was celebrated by many, it also exposed the glaring weakness in Solskjaer's side: the inability to keep clean sheets will certainly be something the Liverpool front line will be salivating over.
Bruno Fernandes has been galvanizing excellent in his past few performances too, creating chances on a whim and will certainly have to be watched carefully in order to keep his influence to a minimum from a Liverpool perspective, should he be fit following his knock in the week.
Man Utd have failed to beat Liverpool in the past six successive attempts, losing three and drawing three.
This is in fact, their longest winless run against Liverpool in the league since a winless seven between December 1989 and October 1992.
The stage is set.
Liverpool Team News
Man of the Match from Tuesday night, Alisson Becker, will have another huge game in between the sticks.
The Brazilian shot-stopper was imposing once again in the Champions League and kept The Reds from falling behind.
Alisson's smart saves against the likes of Joao Felix and Antoine Griezmann before Salah netted the winning penalty were crucial in gaining a very important victory.
Klopp's selection in defence was a strong one against Atleti, going with (what most believe) his strongest backline. Virgil van Dijk will surely start at the weekend, as will Trent Alexander-Arnold and Andy Robertson, but who partners the Dutchman?
Joel Matip is of course the favoured choice: his elite style of play and visible intelligence compliments van Dijk well; he is perhaps the second best CB in the league but questions will also linger over Matip in terms of fitness.
The Cameroonian has enjoyed an injury-free spell this season and has featured heavily for The Reds; with Joe Gomez and Ibrahima Konate waiting, does Klopp stick or twist in his CB rotation?
The midfield in the second half of the first half looked lost at the Wanda Metropolitano Stadium. Joao Felix, Rodrigo De Paul, Koke and Thomas Lemar found pockets of space too easily in the middle of the park and the Liverpool midfield/defence was undeniably exposed at times.
Bruno Fernandes will doubtlessly exploit these spaces and punish The Reds this weekend if this is repeated when the two giants meet.
Naby Keita hit a beautifully struck volley to put The Reds 2-0 to the good on Tuesday, but his defensive frailties were on display and laid bare for all to see.
Keita only won two out of fourteen duels and was partly to blame for both Griezmann goals, letting Lemar and then Felix get away from him too easily.
The Guinean was hooked at half time but in truth, James Milner or Jordan Henderson could fallen to the same fate after their own first half performances.
Keita however, is not a defensive midfielder; he needs a controlling 6 like Fabinho to cover his movements and creative dynamism.
Henderson and Milner showed in Tuesday's game they can not do that against certain opposition and with the elite Fabinho in the midfield three, expect Keita to show his dominance and adroitness once more.
The game in Madrid changed when Fabinho came on; the Brazilian 6 was sensational in breaking down the play and showed a Herculean degree of control in the role he has established as his own.
And so to the weekend, Fabinho surely starts alongside club captain Jordan Henderson, but Klopp has a decision to make in terms of who else.
Curtis Jones has returned to training after his short layoff due to injury (thigh) but Thiago (calf) and Harvey Elliot (ankle) are out.
There were rumours against Watford that Klopp would start a front four, and with Manchester United's lack of quality defensive midfielders themselves, could Klopp just roll the dice and gamble that Liverpool's front four will score more than their rivals attacking players?
"Curtis will train today with us, the full session, that's the plan. And Thiago not. So, these are the two things I know for the moment"
Jurgen Klopp on the midfield injury update
The world seems to have finally seen what all Liverpool fans have proudly stated for a while now: Mo Salah is indeed the best player in the world.
Superlatives have seemingly been exhausted about the Egyptian King's brilliance this season and the only thing left to label the majestic goal-scoring titan… is the best in the world.
Top of the golden boot race with seven goals and four assists and breaking records since his arrival, Salah has now also surpassed Steven Gerrard's Champions League goal-scoring records.
Salah has scored 31 goals - despite having only featured 48 times in the competition. Compared to Gerrard's 30 Salah became Liverpool's highest ever CL goal-scorer.
Salah can break another record this weekend if he scores in the league: he will become the highest ever African goal-scorer, exceeding Didier Drogba's 104 goals in 254 games; Salah will have 105 goals in just 166 games.
Roberto Firmino is enjoying a purple patch of his own this season, scoring a hat trick last weekend to take his tally to four goals in six in the league.
Firmino will be what Manchester United want to avoid this Sunday in terms of his marvelling ability to pull defenders away from their guarded spaces and uncover a pocket of space where Salah and Mane can exploit.
Liverpool will aim to condemn United to a 10th home game without a clean sheet in the Premier League.
United's weakness in their defensive third of midfield is what Firmino thrives on. We saw a lacklustre Watford stand-off Firmino, allowing him to turn and create gaps and intricate passes to begin (and finish) attacks. If Fred, McTominay or Matic do the same, Liverpool's false nine could dictate the open play once again.
Whilst Diogo Jota is a fantastic option in his own right, this game could be made for Bobby Dazzler to set the touch-paper on fire with his catalyst like escalation in attacks.
Sadio Mane has been rejuvenated and reinvigorated this season, the Senegalese Superman(e) has notched an impressive return of six goals in eleven games, the latest goal seeing him joining the PL 100 club.
Mane is also only the third player in PL history to score 100 goals in the competition and none coming from the penalty spot: only Les Ferdinand and former-Red Emile Heskey have achieved that feat before.
Klopp has some options available to him but against Liverpool's greatest adversaries, Klopp will want to go with his strongest possible selection before he surely rotates his Red men against Preston North End in the League Cup next Wednesday.
Manchester United Team News
Marcus Rashford, Bruno Fernandes and Fred picked up injuries on Wednesday nights’ victory and will be assessed before Sunday's game.
Rashford has a tendency to score against Liverpool and his absence would be sorely missed by United, especially since it was he who started the comeback with a typically well placed finish and found the net against Leicester too.
Raphael Varane is still not expected to play as he continues to battle his way back from injury so Victor Lindelof will feature alongside the aerial threat of Harry Maguire.
Lindelof and Maguire are not identified for their scintillating pace, something Mane and Salah will try to capitalise on. Expect the Liverpool attackers to look to play in behind the centre backs rather than compete aerially.
Luke Shaw and Aaron Wan Bissaka will be the men to keep Mane and Salah under lock and key and will have a tough day should they not receive defensive cover from their midfield colleagues.
Wan Bissaka has delivered some sensational long-diagonal balls over the top to Ronaldo, Rashford and Greenwood in recent weeks, something Jurgen Klopp and his defensive high-line needs to be cautious of.
The midfield will always be a contentious enigma for Solskjær until United are able to buy a high quality defensive midfielder to allow the front players the freedom to express themselves fully. Fred and McTominay are not seen as long term solutions in the holding roles if United are going to compete on all fronts this season or indeed future seasons.
Bruno Fernandes is in a class of his own though and is United's own synergist. Since his arrival there has been no other player under Solskjaer to have as much influence in the game than the Portuguese magnifico. The Manchester United boss has stated Fernandes might be a doubt but he will do everything he can to get ready; mind games and crying wolf springs to mind…
United are spoilt for riches in attacking positions; alas, they are yet to find a consistently winning trio in front of Fernandes. Ronaldo is no doubt the first name on the team sheet, but who accompanies him is questionable.
Edinson Cavani is the man who CR7 has replaced in the central striker role but the Uruguayan is still effervescent and full of energy, contributing a great deal for United when he plays.
If Rashford is indeed out injured perhaps Ronaldo moves to the wing and Cavani features up top.
Another option is Greenwood and new boy Jadon Sancho/Paul Pogba (if Fred is fit) flanking Ronaldo.
Mason Greenwood has been in good form, scoring four goals this season and is a direct threat and lethal, Lacey finisher the Liverpool back line will be wary of.
Former Dortmund star Jadon Sancho has struggled to establish himself since his blockbuster £73m move to Manchester, but surely it is just a matter of time before the young prodigy finds his feet in England.
It is the latest battle in the eternal war between English football's most successful sides.
A rivalry built and set against success is what makes this feud so brutally great; there have been challengers to silverware along the way with oligarchs and countries dipping their cash-rich and oil stained hands into the beautiful game we adore, but history is written by the victors of old.
There is no doubt a huge respect for each other from the opposing teams, from the hierarchy of John Henry to the players and fans; respect for each another’s accomplishments has always existed between the two powerhouses - even more so now clubs are being used as puppets for sport washing and political gains.
Perhaps that is why Liverpool versus Manchester United is still English football's most prestigious clash. It is a rivalry built on self-sustained success, rather than success built on cash injections and questionable sponsorship deals.
Jurgen Klopp will want nothing more than three points, even if it is away from fortress Anfield and a rapturous Kop bellowing devotedly about golden skies and a precious life inside the Shankly gates.
Ole Gunnar Solskjaer's fans will be singing their own anthems in full voice as the Reds will strive to match the success of last season at the Theatre of Dreams.
Should Liverpool seal another win in this game, it would be the first time that The Reds have won two in a row against United since a run of three victories in October 2009. Doubters to Believers.
Jürgen Klopp recently celebrated six years at the helm on Merseyside following his appointment on October 8, 2015. Since his arrival, only Manchester City (508) have won more points than the Reds (482); Man Utd from the same number of matches, have only registered 228.
All previous form and stats will get swept away in the crisp autumnal breeze on Sunday though. This is a game which will be won by the team who carries the fire on the day.
That's what makes this sport so uniquely wonderful: anything can happen in the blink of an eye; anything at all.