Erik ten Hag's troops eked out a 1-0 win over Nottingham Forest to progress to the last eight, whereas the Reds' young guns stole the spotlight in a 3-0 fifth-round beating of Southampton.
Match preview
Whether the under-fire Ten Hag will still be in the hotseat at the end of the season is anybody's guess - rumours have swirled that the Dutchman is not viewed as a long-term answer by Sir Jim Ratcliffe - but the ex-Ajax boss could yet lead the Red Devils to two major trophies in as many seasons.
On the back of last season's EFL Cup stardom, the 20-time English champions were too hot for Wigan Athletic and Newport County to handle in the earlier rounds of the FA Cup, and they also navigated a Premier League-sized test in the shape of Nottingham Forest on February 28.
Following 88 scoreless minutes at the City Ground, the deftest of Casemiro touches from a Bruno Fernandes free kick propelled the Red Devils into the quarter-finals of the cup, where they have alternated between victories and defeats in their last eight appearances, losing one quarter-final match then winning the next since 2014-15.
Having made it all the way to Wembley last year, superstition is therefore not on the side of the 2022-23 runners-up, but recent form is more so, as they secured a seventh win from their last nine matches against Everton last weekend, where Fernandes and Marcus Rashford penalties did the damage.
The outcome could have been different had the Toffees managed to convert at least one of their plethora of chances, but profligacy has not been an issue for the Red Devils, who are now on a 13-match scoring streak across all competitions stretching back to Boxing Day.
Speaking of red-clad teams with red-hot attacking tendencies, Liverpool showed no mercy to Sparta Prague during the second leg of their Europa League last-16 tie on Thursday night, where they tore the Czech champions to shreds with an astonishing four goals in just 14 minutes.
Helped by some defensive catastrophes from their visitors, Darwin Nunez, Cody Gakpo, Bobby Clark and the history-making Mohamed Salah all contributed to a barnstorming start, before Dominik Szoboszlai's deflected effort and Gakpo's second sealed a 6-1 win on the night and an 11-2 aggregate success.
With a little over two months of the season left to play, departing hero Jurgen Klopp could still add another three winners' medals to his collection thanks to previous FA Cup wins over Arsenal, Norwich City and Southampton, the latter of which saw academy proteges Lewis Koumas and Jayden Danns (two) sparkle under the Anfield lights.
A 1-1 draw with Manchester City in their Premier League blockbuster means that the title is now officially in Arsenal's hands, although the Gunners - who are only leading Liverpool on goal difference - must trek to the Etihad after the international break, where Reds fans ought to be praying for a stalemate as Gooners were on March 10.
Now unbeaten in nine games and boasting six wins from their last six FA Cup quarter-finals, Liverpool have a couple of wrongs to right against Man United, whom they drew 0-0 with at Anfield in December and lost 2-1 to at Old Trafford in August 2022 either side of their 7-0 Merseyside mauling, the Red Devils' heaviest loss in the Premier League to date.
Manchester United FA Cup form:
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Manchester United form (all competitions):
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Liverpool FA Cup form:
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Liverpool form (all competitions):
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Team News
Just as he was hitting a rich vein of form in England, £72m striker Rasmus Hojlund was cruelly sidelined with a muscular injury, but both Ten Hag and Denmark head coach Kasper Hjulmand have stated that February's Premier League Player of the Month should be back this weekend.
The Red Devils are also optimistic about the fitness of Harry Maguire and Aaron Wan-Bissaka, while long-term calf victim Mason Mount has finally returned to training but may be given more time to get back up to speed with his teammates.
While Hojlund is expected to be given the green light, fellow fledgling attacker Omari Forson is more of a doubt, while Anthony Martial (groin), Luke Shaw (muscle), Tyrell Malacia (knee) and Lisandro Martinez (knee) are still recuperating from their severe issues.
As for Liverpool, Klopp's crop did not come out of Thursday's Sparta slaughter totally unblemished, as first-time goalscorer Clark had to be taken off in the second half with an apparent ankle issue, which the Reds boss admitted he was slightly worried about.
However, Klopp stated last weekend that hamstring victim Ibrahima Konate has a "good chance" of making his comeback at Old Trafford, and Reds fans may also get a glimpse of Ryan Gravenberch, who was back in training before the second leg with Sparta following an ankle injury.
Stefan Bajcetic (calf), Thiago Alcantara (muscle), Diogo Jota (knee), Ben Doak (knee), Joel Matip (knee), Alisson Becker (thigh), Curtis Jones (shin) and Trent Alexander-Arnold (knee) are still missing for the visitors, but Salah - who became the first Liverpool player to net 20 goals in seven straight seasons on Thursday - came through an unplanned 90 minutes unscathed.
Manchester United possible starting lineup:
Onana; Dalot, Varane, Maguire, Lindelof; Mainoo, Casemiro; Garnacho, Fernandes, Rashford; Hojlund
Liverpool possible starting lineup:
Kelleher; Bradley, Konate, Van Dijk, Robertson; Mac Allister, Endo, Szoboszlai; Salah, Nunez, Diaz
We say: Manchester United 1-3 Liverpool
Liverpool are still waiting for their first-ever FA Cup win over Man United at Old Trafford, and no sheets should be clean at the Theatre of Dreams this weekend, as the Reds work around a shortened recovery period against Ten Hag's free-scoring troops.