Thornber has been at the helm for the Millers' last two games following the departure of Mark Robins, but will stand aside following the appointment of Ronnie Moore.
And Thornber has a fully-fit squad to choose from as he looks for a first win of his short tenure following draws against Morecambe and Cheltenham.
In-form striker Adam Le Fondre had been a doubt with a niggle, but he has come through training and will be fit to continue his blossoming partnership with Tom Pope.
Midfielder Nicky Law and Ian Sharps have also shaken off minor injuries and look set to be involved.
Moore, who was appointed to the Millers hot seat for the second time four years after leaving the club, will watch from the stands at Don Valley and will take charge of the team for the first time in Tuesday's clash at Northampton.