A draw, or better, would move Jürgen Klopp's men ahead of current leaders Manchester City, with 11 league games left to play until the end of the season.
The Reds beat United 3-1 at Anfield earlier this term but there is a new man in the United dugout - the third Red Devils manager Klopp will have faced since arriving at Liverpool in 2015 - and new impetus on the pitch.
Ole Gunnar Solskjaer's attack-minded approach has yielded eight victories during a nine-match unbeaten run in the league and Sunday's encounter against a Liverpool side that have outscored all but City this season threatens to be a real thriller.
We've picked out three key player battles that could help decide the match...
Romelu Lukaku v Virgil van Dijk
Having sat out Tuesday night's 0-0 draw with Bayern Munich due to suspension, centre-back Virgil van Dijk heads to Old Trafford fresh, rested and looking to reprise his dominant display from the reverse fixture in December.
The Dutch centre-back helped limit opposite number Romelu Lukaku to just 20 touches of the ball at Anfield, with seven of those coming in the United striker's own half.
Lukaku will hope to receive better service this time around, but the 6ft 2in striker will still face a real battle to get the better of an equally imposing player that can also match him for pace and technical ability.
Van Dijk has played more minutes in the Premier League than any of his outfield colleagues at Liverpool this term, helping to keep a league-leading 14 clean sheets in the process.
Lukaku, meanwhile, is still seeking to rediscover the form that made him United's top scorer with 27 goals in 2017-18.
The Belgian international has nine this term, with three of those coming in his 11 outings under Solskjaer. Arguably his best performance under the new regime came against Arsenal at the end of January when he provided a brilliant pair of assists in a 3-1 win.
Paul Pogba v Georginio Wijnaldum
With eight goals and five assists in his nine Premier League matches under Solskjaer, Paul Pogba is one of the most in-form players in the top flight at present.
Restored to the position in which he did so much damage at Juventus - on the left of a midfield three - the French World Cup winner has been revitalised.
Goalscorer, creator and destroyer all in one, the 25-year-old has become central to the way United play.
Lining up for Liverpool against Pogba will likely be Georginio Wijnaldum, who is enjoying an excellent season himself.
Wijnaldum's all-action midfield display against Man Utd
Despite the arrival of Naby Keita and Fabinho in the summer, the Dutch international has stepped up to become one of the mainstays of Klopp's midfield.
Back in a more attack-minded role recently, often playing as Liverpool's most advanced midfielder, the 28-year-old will be aiming to keep Pogba busy tracking back towards his own goal, but is more than capable of doing a defensive job if required.
He was a dominant force when the two clubs met in December and if he can repeat that on Sunday it will go a long way to giving his side the upper hand.
Victor Lindelof v Roberto Firmino
With Mohamed Salah tending to revert to his wider role for the bigger away games it could well be Roberto Firmino who is charged with terrorising the United centre-backs.
The Brazilian has largely played a more withdrawn, creative role this season but has still managed to net 11 times in all competitions.
The No.9 set up Xherdan Shaqiri for the final goal in the sides' previous showdown in December, against a United defence that featured Victor Lindelof.
The Sweden international and his colleagues couldn't cope with Liverpool's attacking trio that day, but he has since developed into one of the unsung heroes of Solskjaer's revolution.
The much-improved Lindelof was shortlisted for Premier League Player of the Month for January after a series of impressive performances and is now an automatic choice in the centre of defence.
The ball-playing centre-back likes to build attacks when in possession but also loves a tackle. That combination, plus his pace and excellent reading of the game, makes him a tough opponent to beat.
But he will certainly have to be at his best to subdue a Firmino-led trio - along with Salah and Sadio Mane - that have scored 38 times in the Premier League this season.