Thirlwell sustained a calf injury in the midweek win at leaders Doncaster and was replaced by Danny Cadamarteri.
Manager Greg Abbott has no other new injury or suspension worries as his side chase a third straight league win.
But defender Frank Simek, who has missed the last two games due to a thigh injury and winger Matty Robson, sidelined for the last three with a back problem, are expected to miss out again.
Defenders Peter Murphy and Mike Edwards, strikers Rory Loy and Mark Beck and recent signing Mathieu Manset are all pushing for recalls as the Cumbrians look to extend their unbeaten run to six matches.
- Sports & Recreation
- Matty Robson
- Frank Simek