Frank Lampard welcomes the Red Devil’s to West London with the Blues on an exceptional run of form, whilst their opponents are showing signs of improvement.
Getting into the fourth round was easy work for the Blues. A 7-1 battering of Grimsby Town in the previous round proved to be a breeze, but for Manchester United it was anything but easy.
Ole Gunnar Solskjær's side scraped into the fourth round to set up an away tie with Chelsea after a penalty shootout victory against League One side Rochdale. At Old Trafford too, the Red Devils could only manage a 1-1 draw after 90 minutes, and narrowly secured a 5-3 victories on penalties.
They'll face an even tougher test at Stamford Bridge as Chelsea will look to get revenge from the unflattering scorelines they got at Old Trafford on the opening day of the season.
The perfect hat-trick - left foot, right foot and a header - marked Chelsea to a seventh consecutive win all competitions heading into the clash with Manchester United.
Opponents Manchester United also tasted victory, this time on the road, against Norwich City in a 3-1 victory at Carrow Road.
Marcus Rashford and Anthony Martial were back on the scoresheet for Manchester United, but they both each missed a penalty on Sunday, showing areas of weakness to Chelsea.
Frank Lampard will be without N'Golo Kante [groin] and Andreas Christensen [hamstring[ as the pair continue their recoveries from their respective injuries. Ruben Loftus-Cheek remains out.
Antonio Rudiger could make an appearance for the Blues on Wednesday as he looks to step up his return to full fitness.
Ross Barkley has been absent for Chelsea's previous two fixtures, but could see himself back in contention to face Manchester United.
Callum Hudson-Odoi was favoured to start on the bench against Burnley on Saturday, which could see him then start at Stamford Bridge on Wednesday.
Manchester United will be without Paul Pogba, after it was confirmed the Frenchman will be out until December.
Former Blues Nemanja Matic could face his former side as he could return to the United side to face Chelsea, but he remains a major doubt.
Ole Gunnar Solskjær's Manchester United team have the bragging rights so far this season against Chelsea after the opening day 4-0 win against Chelsea at Old Trafford in the Premier League.
Perhaps a scorelines which didn't portray a true reflection of the game, but United showed their ruthlessness in front of goal and dealt Frank Lampard's a major blow.
Chelsea are winless in four against Manchester United in all competitions [D2, L2], which will give the visitors' confidence heading into the cup tie.
The last victory for the Blues came in the 2018 FA Cup Final as Eden Hazard's first-half penalty landed Chelsea another piece of silverware.
Chelsea are in a rich vein of form, whilst Manchester United look extremely bleak in front of goal, despite their three goals against Norwich.
Momentum, confidence, and no fear breaths through the young Chelsea side, and with only two victories on the road all season for Ole Gunnar Solskjær's men, they could see themselves crashing out of the Carabao Cup early on, comes the full-time whistle on Wednesday at Stamford Bridge.
But back-to-back wins on the road for United will spur the Red Devils on to continue their form at Stamford Bridge.
Prediction: Chelsea 3-1 Manchester United