Carlisle United could be without captain Paul Thirlwell for up to four weeks after a scan on Thursday revealed a calf tear.
The 33-year-old picked up the injury in Monday's 4-0 League One defeat by Brentford, his 29th appearance of the season for Greg Abbott's side.
Thirlwell joined Carlisle from Derby County in January 2007.
Meanwhile Rory Loy has had pins removed from the lower leg .
Former Rangers striker Loy, 23, is expected to be able to walk without crutches within a fortnight.