The Hammers forward is on the brink of returning from a hamstring injury, but given his past struggles it would be dangerous to bring him back too soon.
Fabian Balbuena starts at Bramall Lane after the in-form defender only arrived back late on Thursday after internatonal duty with Paraguay, while Angelo Ogbonna has shaken off a groin injury to take his place in defence.
One player Moyes has no concerns over after the international break is Declan Rice. The Hammers midfielder excelled with the Three Lions and his manager says the 21-year-old is maturing at quite a rate.
"The big thing is that he is improving," said Moyes. "He is learning a lot from the people he has been playing around. I thought his performance for England the other night was exceptional, there was a lot of talk about the other young English talent but I thought, on the night, Declan was as good as anyone.
"His performance was so good. He is maturing, he is picking up from a lot of good people like Mark Noble, Harry Kane, the leadership that is required so I think for Declan and his point of view it is continuing to learn, seeing what good practice looks like, seeing what good leaders look like and I think that being captain of West Ham at such a young age helps.
"We are trying to get him to take more responsibility, more leadership."
Sheffield United starting XI: Ramsdale, Basham, Egan, Fleck, Baldock, Berge, Norwood, Ampadu, Lowe, McBurnie, McGoldrick
Subs: Lundstram, Burke, Jagielka, Robinson, Verrips, Osborn, Brewster
West Ham starting XI: Fabianski, Coufal, Ogbonna, Balbuena, Cresswell, Masuaku, Rice, Soucek, Bowen, Fornals, Haller
Subs: Randolph, Diop, Johnson, Noble, Snodgrass, Lanzini, Benrahma