The managerless Mancunians suffered another fitness blow on Sunday afternoon during the defeat at West Ham United, with Noussair Mazraoui forced off following a nasty collison with Jarrod Bowen.
With the former Bayern Munich defender a doubt for this match, Diogo Dalot and Lisandro Martinez are set to operate in the full-back roles for the hosts.
Harry Maguire (ankle) and Leny Yoro (foot) remain on the sidelines for Man United, meaning that Matthijs de Ligt and Victor Lindelof should start as the centre-back pairing.
Summer signing Manuel Ugarte failed to feature at the London Stadium but should earn a chance on Wednesday night in the absence of England star Kobbie Mainoo (muscle).
Available and raring to go, Bruno Fernandes is a certainty in the advanced-midfield role, whilst Amad Diallo should be promoted from the bench for this cup tie.
Playing second fiddle in the Premier League to Rasmus Hojlund recently, Joshua Zirkzee will be targeting a morale-boosting performance at the tip of the Man United attack versus the relegation-threatened Foxes.
Manchester United possible starting lineup: Onana; Dalot, De Ligt, Lindelof, Martinez; Ugarte, Eriksen, Diallo, Fernandes, Garnacho; Zirkzee
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