The two most successful cubs in the English game face off as Manchester United travel to Anfield top of the table thanks to their 1-0 win at Burnley on Tuesday night after Liverpool picked up just two points from their last three Premier League games.
Draws against West Bromwich Albion and Newcastle United were followed up by the disappointing 1-0 defeat to Southampton at St. Mary's as the Reds ended the old and started the new year in slow fashion, scoring just one goal in the three Premier League matches.
But last Friday's 4-1 win over a youthful Aston Villa side in the FA Cup will have fed new life into Liverpool veins ahead of Jürgen Klopp's 200th game as manager - his 100th at Anfield - and, having only lost four home games in the German's reign, they'll be expecting a big performance to reclaim top spot from their fiercest rivals.
United, meanwhile, have seen a massive resurgence of late. Ole Gunnar Solskjær's men haven't lost in the league since Arsenal took all three points from Old Trafford on November 1st, winning nine of their last 11 league matches.
With the likes of Marcus Rashford, Bruno Fernandes and even Paul Pogba in the goals - and providing them - in each of their last six league games, the Red Devils are starting to believe again. However, the shaky 1-0 FA Cup win against Watford showed there are still weaknesses that can be exploited.
As far as Liverpool are concerned, there's no major news to report. Virgil van Dijk and Joe Gomez are still sidelined for months and Diogo Jota won't be in the fold for a few weeks yet. Having played at center half regularly this season, Fabinho is expected to drop into the back line once more, leaving captain Jordan Henderson to fight in the holding midfield role.
Joel Matip is in contention to start the game and Jürgen Klopp said the German 'is close' to full fitness. Matip will be involved in training sessions on Friday and Saturday before Klopp makes his decision.
Naby Keita is definitely not fit. "It's not a big thing", says Klopp. "He came back [from injury], played a lot of games and now has a small injury so because we have alternatives in midfield, we said 'no'."
The big remaining question mark is whether Thiago Alcantara will start in the midfield three. The Spanish playmaker has been brilliant every time he's pulled on the red shirt and ran the game against Villa on his return from injury.
It's a similar story for United. Paul Pogba's deflected volley sent them top of the pile in midweek, so he's put his name forward for a starting spot in some style, but Fred and Scott McTominay may be best suited as the visitors try to combat their hosts' physical midfield. Those two have both shown impressive consistency in United's long unbeaten run in the league, so maybe they'll both start.
One area of concern for Solskjær is the injury to Eric Bailly sustained in their home win against Watford last weekend. The Ivorian defender played the full ninety minutes at Turf Moor on Tuesday night, but the lasting effects could show against Liverpool's incredible strike force.
There have been 232 titanic showdowns between the two clubs through the years, with United leading the way with 88 wins, but Liverpool have been coming out on top of late and haven't lost to their arch-rivals since the 2-1 away defeat in March 2018.
Since then, the Reds have won two from four with Xherdan Shaqiri and Mohammed Salah starring in 3-1 and 2-0 triumphs in front of the Kop. The Swiss international came on and stole the show with two second-half strikes in December 2018, whilst the Egyptian king sealed a massive victory in the two sides' last meeting - racing through from his own half thanks to Alisson's long ball before calmly slotting the ball under David de Gea. That was the moment they knew the league title was heading their way.
You have to go back to 17 January 2016 - five years ago to the day - for the last time Man United took all three points from Anfield. Wayne Rooney netted the only goal of the game with twelve minutes left.
Marcus Rashford has a habit of scoring in this fixture. He netted in last season's controversial 1-1 draw at the Theatre of Dreams and struck both goals in the aforementioned win in 2018.
Only once before have the two most successful sides in English football gone head to head for the Premier League crown. In 2008/09, Liverpool won both meetings and were top at the turn of the year, but Manchester United prevailed come the final day.
Ryan Babel scored the winning goal in a 2-1 home victory at Anfield and the reverse fixture is arguably their greatest-ever way day.
The traveling scousers feared the worst when they conceded to a Cristiano Ronaldo penalty midway through the first half, but Fernando Torres made a mockery of Nemanja Vidić before club legend Steven Gerrard buried a spot-kick of his own to turn the game on its head.
From there on in, Liverpool dominated. Fábio Aurélio bent a beautiful free-kick into the top corner and Andrea Dossena, the most unlikely of scorers, dispatched a perfectly-measured lob over Edwin van der Sar to round off the 4-1 demolition job at Old Trafford and reignite the title race.
Players to watch
Bruno Fernandes has been one of the Premier League's standout performers since his arrival from Sporting Lisbon in last season's January transfer window. Averaging a direct goal involvement in almost every game, the Portuguese maestro will undoubtedly be the main cause of concern for the home defence.
Both sides boast world-class wingers in Marcus Rashford, Sadio Mané and Mohammed Salah. They have all scored in this fixture before, so it will be interesting to see which of those three incredible talents deliver on the big stage again on Sunday.
Finally, the two 'keepers. Along with Ederson, Alisson and De Gea have been in the 'best goalkeper in the world' debate for years. Both are capable of world-class, logic-defying saves and they'll have to be at their best to keep a clean sheet in this one.
How to watch
The showdown kicks off at 16:30 (GMT) and will be broadcasted live on Sky Sports in the UK.
What the managers have to say
Jürgen Klopp spoke to national media ahead of his 200th match in charge of Liverpool and, when questioned on whether the prospect of losing and dropping six points behind United or winning to move back to the top of the league makes a difference to his preparations, he had this to say:
"Playing against United is enough [motivation]. We play at home against United and we want to win, so that's all we have to think about.
"There's no extra add ons in this situation. They deserve the points that they have so far and we have ours. The season still has a long way to go. We just try to win our football games."
Speaking about Marcus Rashford's work with free school meals and child poverty, Klopp was full of praise.
"I've said it before and I'll say it again, his work is exceptional. He has been given honours for it and that is absolutely right.
"I know that he is sad that he has to do it, because this should already be there, but he had the same beginning as a kid and it is amazing to see someone never forgetting their roots."
Ole Gunnar Solskjær also spoke to the press, saying form is irrelevant when his side face Liverpool, despite travelling to Anfield top of the table.
"You are always excited when you are going to play against teams of that quality," said Solskjær.
"Form goes out of the window and it doesn't matter. When you go to Anfield, it's a big game for the club, the players and the fans. I'm looking forward to it.
"You don't get anything for being at the top of the league in January. It's not ever something we have valued, or ever will. It's where you end up at the end of the season that matters."