The Ulsterman reported a tight calf after Saturday's game against Plymouth Argyle and was treated yesterday. Gary Deegan will deputise if Clingan does not respond to treatment.
Leon Barnett is available after serving a two game suspension and with vital games at Leicester on Sunday and West Brom next Wednesday, Chris Coleman may make changes in the squad.
Clinton Morrison will make his 450th league appearance if he plays for City who have only beaten Cardiff once at home in a League game in 46 years.
For Cardiff, City old boy Jay Bothroyd is expected to play whilst Nuneaton born Peter Whittingham and Tony Capaldi could make their 200th appearance alongside Gavin Rae who could play his 400th club game.
Cardiff boss and former Sky Blue David Jones, has Michael Chopra suspended and Kevin McNaughton rated as doubtful due to a thigh problem. Gabor Gyepes could return to the squad after missing the 1-0 defeat at Leicester on Saturday.
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