The Red Devils secured a 3-1 victory over Everton in the third round to set up a contest with the Royals, who beat fellow second-tier side Watford 2-0 on home soil.
Match preview
Man United have moved one step closer to winning their first trophy since 2017 after securing a 3-0 away victory against Nottingham Forest in the first leg of the EFL Cup semi-finals on Wednesday night.
January loan signing Wout Weghorst scored his first goal for the club either side of strikes from Marcus Rashford and Bruno Fernandes to give the Red Devils a commanding three-goal advantage heading into the second leg at home next week.
Focus now shifts to the FA Cup for Erik ten Hag's side, who enter Saturday's contest in fine form on home soil after winning each of their last 10 games at Old Trafford across all competitions, scoring 26 goals and conceding only four in the process.
Man United, who sit fourth in the Premier League table, are also unbeaten in their last 14 home matches in the FA Cup, including two third-round victories against Reading in the last six years - winning 4-0 in 2017 and 2-0 in 2019.
The Red Devils have in fact progressed from nine of their 10 FA Cup ties against the Royals, but they cannot take their Championship opponents lightly on Saturday, after being eliminated on penalties by second-tier side Middlesbrough in the fourth round last season.
Since beating Watford in the FA Cup third round three weeks ago, Reading have failed to win their last two Championship games and have conceded six goals in the process, with a 2-2 draw at home to Queens Park Rangers followed by a 4-0 thumping by Stoke City last weekend.
The Royals, who have spent the last 10 years in the second tier, have subsequently slipped to 14th in the table and five points behind the playoff positions, while there are no immediate fears of relegation as they sit 11 points clear of the bottom three.
Paul Ince will return to familiar territory on Saturday when he takes his Reading side to former club Man United, where he spent six years as a player and won 10 trophies, including two FA Cups in 1990 and 1994.
Reading have never lifted the FA Cup in their 151-year history and have failed to progress beyond the fourth round in five of the last six years, including an embarrassing third-round exit to non-league side Kidderminster Harriers last season.
Hopes of causing an upset against Man United on Saturday appear to be slim for the Royals, who have lost seven of their last eight FA Cup ties against Premier League opposition, while they have only won one of their previous 22 meetings against the Red Devils across all competitions - that victory was in the FA Cup, though, winning a third-round replay 2-1 back in 1927.
Manchester United FA Cup form:
W
Manchester United form (all competitions):
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W
W
D
L
W
Reading FA Cup form:
W
Reading form (all competitions):
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D
L
W
D
L
Team News
Man United duo Axel Tuanzebe and Jadon Sancho have returned to training but are not yet ready to feature for the first-team, while Donny van de Beek is ruled out for the rest of the season with a knee injury.
After missing the win over Forest, Luke Shaw (illness), Anthony Martial (leg) and Diogo Dalot (hamstring) all remain doubtful and will be assessed ahead of kickoff this weekend.
Harry Maguire is available to return after serving a one-match ban in midweek and the centre-back could be handed a start at the expense of either Lisandro Martinez or Victor Lindelof, while goalkeeper David de Gea could be rested, with either Tom Heaton or Jack Butland taking his place between the sticks.
Indeed, Ten Hag is expected to rest a number of his first-team stars, which could open the door for the likes of Alejandro Garnacho, Anthony Elanga, Facundo Pellistri and Kobbie Mainoo to be handed a start.
As for Reading, they will be without Andy Carroll (ankle), Naby Sarr (knee), Sam Hutchinson (Achilles) and Liam Moore (hamstring) due to injury, while Ovie Ejaria is set to remain away from the first-team fold having allegedly been told to leave the club this month.
Teenage right-back Kelvin Abrefa, who scored in the third-round victory against Watford, recovered from a knee problem to feature for the club's Under-21s on Monday and he could be involved in the senior matchday squad on Saturday.
Lucas Joao, Shane Long, Scott Dann and Nesta Guinness-Walker, who all began on the bench against Stoke, will be hoping to force their way back into the first XI.
Manchester United possible starting lineup:
Heaton; Wan-Bissaka, Lindelof, Maguire, Malacia; McTominay, Fred, Mainoo; Elanga, Weghorst, Garnacho
Reading possible starting lineup:
Lumley; Yiadom, Holmes, McIntyre; Hoilett, Hendrick, Fornah, Loum, Baba; Ince, Joao
We say: Manchester United 3-0 Reading
Man United will be regarded as firm favourites to progress to the fifth round, even if Ten Hag does decide to rest a number of first-team regulars.