English football's two most successful clubs have been paired in the competition 12 times, United dominating with nine wins to Liverpool's three.
Here, we look at five of their classic FA Cup meetings.
1976-77: Man Utd 2 Liverpool 1 (Final)
Liverpool were chasing the Treble and had already won the league title before turning up at Wembley on May 21, 1977.
Bob Paisley's side had a European Cup final date against Borussia Monchengladbach four days later, but the second part of their mission was ruined as United sprang a surprise.
The three goals came in a four-minute spell at the start of the second half, with Stuart Pearson firing United ahead before Jimmy Case equalised brilliantly.
Two minutes later Tommy Docherty's United were back in front when Lou Macari's drive deflected off Jimmy Greenhoff's chest.
Liverpool went on to win their first European Cup in Rome, but United became the first English club to win the Treble of league, FA Cup and European Cup 22 years later.
1995-96: Man Utd 1 Liverpool 0 (Final)
The brightest thing about the 1996 final was Liverpool's cream suits as the so-called 'Spice Boys' served up a pre-game fashion blunder. On the pitch, United were the trendsetters with Sir Alex Ferguson's side having overtaken Newcastle in the final straight to win the Premier League title and were chasing a second Double in three seasons. The May 11 clash was a tight affair of few chances. But, with five minutes remaining, David James tried to punch a corner clear and the ball fell to the feet of Eric Cantona. The maverick French forward delivered an unerring finish to take the cup back to Old Trafford for the ninth time.
1998-99: Man Utd 2 Liverpool 1 (Fourth round)
The fourth-round clash at Old Trafford on January 24, 1999 was billed as the battle of the strikers, with United's in-sync double act Andy Cole and Dwight Yorke taking on Liverpool's sharp-shooters Michael Owen and Robbie Fowler.
It was advantage Liverpool when Owen headed them ahead after three minutes.
United turned the screw in the second half with captain Roy Keane hitting the post twice.
Just when it looked as if was not going to be United's day, Yorke equalised two minutes from time.
Super-sub Ole Gunnar Solskjaer, the current United manager, then scored a dramatic winner to send Old Trafford wild.
2005-06: Liverpool 1 Man Utd 0 (Fifth round)
Peter Crouch was the man responsible for pitting the Premier League's top two together at the fourth-round draw on Monday evening.
Crouch found himself in the doghouse with his Liverpool-supporting father-in-law, but 15 years ago he was the hero on the red half of Merseyside with his fifth-round winner at Anfield.
Crouch headed home Steve Finnan's cross after 19 minutes to give Rafael Benitez's side a deserved place in the quarter-finals.
It was Liverpool's first FA Cup win over United in 85 years and United's misery was compounded as substitute Alan Smith suffered a broken leg in bizarre circumstances, blocking a free-kick, late on.
2011-12 Liverpool 2 Manchester United 1 (Fourth round)
The build-up to the fourth-round clash on January 28, 2012 - the last time the two clubs met in the FA Cup - was dominated by an incident involving Liverpool striker Luis Suarez and United defender Patrice Evra in the Premier League game at Anfield the previous October.
Suarez had been banned for eight games by the Football Association for racially abusing Evra.
Daniel Agger headed Liverpool into a 21st-minute lead, but Park Ji-sung levelled with a powerful shot before half-time.
The tie seemed destined for a replay at Old Trafford before Dirk Kuyt struck two minutes from time to send the Reds into the last 16.
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