The third-round battering of League One Barnsley turned out to be the penultimate victory of Erik ten Hag, who was relieved of his managerial duties on Monday morning.
The Red Devils come into this clash sitting 14th in the Premier League table following a controversial 2-1 loss at the home of West Ham United on Sunday afternoon.
Here, Sports Mole rounds up Man United's injury and suspension news ahead of their contest with Leicester, who will be looking to take their minds off a relegation battle with victory at the Theatre of Dreams.
Noussair Mazraoui
Status: Major doubt
Type of injury: Knee
Possible return date: Unknown
Mazraoui was forced off with a knee complaint following a nasty collison with Jarrod Bowen on Sunday, with the full-back currently being assessed ahead of EFL Cup duty on Wednesday.
Antony
Status: Major doubt
Type of injury: Ankle
Possible return date: Unknown
Forced off on a stretcher during the draw with Fenerbahce in the Europa League last week, Antony did not feature at the London Stadium versus West Ham and remains a serious doubt for Wednesday night.
Leny Yoro
Status: Out
Type of injury: Foot
Possible return date: December 3 (vs. Arsenal)
Although back on the grass at Carrington, Yoro is still a while away from first-team action for his new employers after breaking his metatarsal during pre-season.
Tyrell Malacia
Status: Out
Type of injury: Knee
Possible return date: Unknown
After missing the entirety of last season, left-back Malacia is targeting a return to action in the near future but is unlikely to be rushed back into the fold by Van Nistelrooy.
Luke Shaw
Status: Out
Type of injury: Calf
Possible return date: Unknown
Last kicking a competitive ball for Man United in February, Shaw is in the closing stages of his return from a troublesome calf injury and should feature before the end of the calendar year.
Kobbie Mainoo
Status: Out
Type of injury: Muscle
Possible return date: November 24 (vs. Ipswich Town)
A muscular problem has kept England prodigy Mainoo on the sidelines in recent weeks, with the midfielder targeting a place in the squad for the trip to Ipswich in late November.
Mason Mount
Status: Major doubt
Type of injury: Head
Possible return date: Unknown
Despite Ten Hag failing to rule Mount out of the West Ham clash, the former Chelsea star was nowhere to be seen at the London Stadium and is therefore a major doubt for the visit of Leicester.
Toby Collyer
Status: Major doubt
Type of injury: Knock
Possible return date: Unknown
Enjoying a breakthrough campaign in the first team early on in the campaign, Collyer has not featured in a Man United squad since the 3-3 draw at Porto in the Europa League on October 3.
Harry Maguire
Status: Out
Type of injury: Muscle
Possible return date: November 10 (vs. Leicester City)
Ten Hag confirmed that Maguire will be sidelined for "a few weeks", meaning that the Red Devils will be short of options at centre-back on Wednesday night.
MANCHESTER UNITED'S SUSPENSION LIST
Man United have no players suspended for this EFL Cup match.