Murphy has missed the last two games after sustaining a groin injury in the recent win at Bournemouth and Forte has been sidelined for the last four matches with a similar problem.
The Blades will also be boosted by the return of defender Danny Higginbotham, who missed last weekend's win at Oldham through illness, so manager Danny Wilson must decide whether to retain Matt Hill in his back four.
Teenage striker Diego De Girolamo, pushing for his full debut in recent weeks, is out after sustaining injury while on international duty with Italy Under-18s in midweek.
The Blades are bidding to return to the top of the table by extending their unbeaten run to seven games. They have dropped only two points in their last six.