Hull City may have to play without a recognised centre-half as they take an already limited squad to Old Trafford for the first leg of the EFL Cup semi-final.
Central defenders Michael Dawson, Curtis Davies and Harry Maguire are all injury doubts for the game due to injury.
Dawson picked up a shoulder injury in Saturday's FA Cup victory over Swansea City, while Curtis Davies will definitely miss out and Harry Maguire is also doubtful.
Despite injuries to key players, Marco Silva believes that Hull can beat United over two legs, but did concede that United are clear favourites for the tie.
"I think it's a different challenge [to the Swansea match]. Okay, it's not a miracle, I believe, and I am sure Man United are favourites but they need to, they want to, prove this in the pitch and we will try to do the same.
"To get to the final is not easy. Man United is the favourite but we will do our best to be in the final".