Mellis has been a virtual ever-present for manager Keith Hill this season, but sustained a dead-leg in last week's heavy defeat at Watford and is rated as very doubtful.
Teenager Reuben Noble-Lazarus, Stephen Dawson, Tomasz Cywka and Jim O'Brien will all be hoping to return to the starting line-up in Mellis' expected absence.
Another midfielder, David Perkins, remains sidelined with a hamstring problem, but Hill has no other new injury or suspension problems and apart from a replacement for Mellis has hinted he will not be making changes.
On-loan trio Akos Buzsaky, Jonathan Greening and Emile Sinclair are expected to start again.
But striker Mido is still not in contention following a back problem as the South Yorkshire side chase their first league win in 10 matches.