Thorn was City's major absentee for Saturday's 2-0 M69 derby defeat at Leicester having been laid low with a virus, with assistant manager Steve Harrison taking charge.
But Thorn is expected to be back in control of team affairs at the Ricoh Arena as the Sky Blues look to boost their survival hopes.
City are likely to boast pretty much the same squad of players as they did at the weekend.
Sammy Clingan, Cody McDonald and Nathan Cameron continued their comebacks on the bench but there was no place for fellow returning duo Chris Hussey and Conor Thomas.
Defenders Richard Wood (knee) and Hermann Hreidarsson (shoulder) continue to miss out.