Thirlwell, who missed Saturday's win over Bury, has been dogged by injury this season and after a recent return from a calf problem was forced out of the Boxing Day win over Hartlepool after a recurrence of the same problem.
Chris Chantler shook off a knock to his ankle to last the full 90 minutes against Bury and is expected to continue, while fellow midfielder James Berrett (groin) is hoping to start again. He returned to the starting line-up against Bury after a four-game absence and lasted 67 minutes.
Veteran striker Danny Cadamarteri remains sidelined with a calf injury he sustained recently in training.
The Cumbrians secured back-to-back victories for the first time this season on Saturday and climbed eight points clear of the relegation zone.