Morgan is struggling to shake off a "knock" and Montgomery has a "strain" and both players will be assessed on the morning of the game.
Central defender Matt Kilgallon could be back in contention following a chest infection as he will make the trip.
Striker Ward tore a hamstring in last Friday's derby win over Sheffield Wednesday and is expected to be sidelined for six weeks.
Manager Kevin Blackwell is undecided on whether to play one of either Ched Evans or Darius Henderson on their own up front, or both together in a 4-4-2 formation. Otherwise, the Blades boss has no other new injury or suspension problems as his side chase their fifth league win of the season.
Jonathan Fortune could feature after signing a short-term deal.