Sharp did not feature in last weekend's 2-0 FA Cup defeat to Notts County and the 10-goal forward has been the subject of frenzied transfer speculation, with a number of clubs thought to be chasing his signature.
Leicester had an offer for the 25-year-old accepted this week before Doncaster responded by offering Sharp a lucrative new contract.
Defensive midfielder Damien Plessis finally received international clearance on his loan move from Panathinaikos on Wednesday and is available for selection along with Herold Goulon, who has shaken off a hamstring problem.
Saunders' midfield options could be further boosted by the returns of Martin Woods and John Oster, who appeared from the bench against Notts County following lengthy spells on the sidelines with respective groin and neck problems.
Rovers have mixed news in defence this week as Shelton Martis returns from a groin injury, but Pascal Chimbonda remains out due with his hip problem and George Friend is facing a month in the treatment room due to medial ligament damage.
Cardiff will be without striker Rudy Gestede and Kevin McNaughton for the trip to South Yorkshire.
Gestede missed the 1-0 defeat to Crystal Palace in the Carling Cup semi-final first leg on Tuesday with an twisted ankle picked up during the FA Cup third-round clash with West Brom last weekend.
The Frenchman, who has struggled with a succession of injuries this term, is unlikely to be available to manager Malky Mackay in South Yorkshire.
McNaughton hobbled off at Crystal Palace in midweek.
Other than that, however, Mackay has no new concerns ahead of the trip to the Keepmoat Stadium.
Meanwhile, goalkeeper David Marshall could be restored between the sticks after being rested for the two recent cup encounters, with Tom Heaton making way.