The Republic of Ireland stopper has missed the past two games having been forced off with a back injury against West Brom that has proved more serious than first expected. But Chris Coleman will only include him if he is 100% fit, meaning Dimi Konstantopoulos remains on standby to continue.
Central defender Ben Turner (ankle) and midfielder Isaac Osbourne (knee) are certain to miss out while captain Stephen Wright is still shaking off the effects of a recent flu bug but may be involved.
A battle-scarred Sky Blues backline has received some positive news this week with the arrival of Richard Wood on loan from Sheffield Wednesday. And he could line up for the first time alongside fellow loanee Leon Barnett, who is in line for his home debut, depending on Wright's availability.
Left-back Marcus Hall has returned to training following the recent death of his father and is back in first-team contention.
Midfielder David Bell will be hoping for more game time after his recent return from injury but defender James McPake is still working on his match fitness, while Sammy Clingan (broken toe) hopes to be back in around a week. Teenage defender Jordan Clarke also serves a one-match ban.
Paddy McCarthy looks set to miss out for Crystal Palace.
The centre-half has been sidelined for the last three games with a shoulder injury which will eventually require surgery.
He has been given the green light to resume playing as the problem will not get any worse, but Eagles boss Neil Warnock is likely to hold him back for at least another week so Claude Davis and Jose Fonte will continue at the back.
Young winger Sean Scannell suffered a hamstring injury playing for the Republic of Ireland Under-21 side last weekend and will also be missing.
Striker Calvin Andrew is stepping up his return from a cruciate injury but is some way from full fitness, while midfielder Kieran Djilali has joined Chesterfield on a month's loan.
Sporting Life