Carlisle will be without Lubo Michalik for their home game with Brentford.
The big central defender is away on international duty with Slovakia, so manager Greg Abbott is expected to switch to a flat back four with Danny Livesey partnering Peter Murphy at the heart of defence.
Abbott told the News & Star: "You can see the positive and negative sides of the big man being called up, but it's up to the players to get on without him against Brentford."
Abbott, who has no new injury or suspension problems, has employed three central defenders in the Cumbrians' last two matches, but could be tempted to switch to a 4-4-2 formation.
Midfielders Tom Taiwo and Jon-Paul McGovern are pushing for returns to the starting line-up, as is striker Francois Zoko.
Abbott's side have lost all three league games they have played without Michalik this season.
Brentford will check on Karleigh Osborne ahead of the trip.
The centre-half missed Wednesday night's 3-0 Johnstone's Paint Trophy win at Charlton due to a slight groin problem, with Miguel Llera stepping into the back four.
The Bees will be without midfield duo Niall McGinn, who is on international duty with Northern Ireland, and Marcus Bean following his first call-up to the Jamaica squad.
Boss Uwe Rosler has a few selection dilemmas after making five changes at The Valley.
Richard Lee will return in goal and Clayton Donaldson should reclaim his place in attack.
Defenders Leon Legge (hamstring) and Shaleum Logan (ankle), winger Kirk Hudson (hip) and striker Gary Alexander (knee) are still on the causalty list.
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