Carl McHugh will miss City's home game with Tranmere on Sunday after being called into the Republic of Ireland under-21 squad.
McHugh was on the standby list for the Euro Championship double header against Romania and has now been promoted for the home and away ties on Friday and next Tuesday.
With Rory McArdle away with Northern Ireland, that leaves Phil Parkinson short of cover at centre half for the weekend.
Luke Oliver will replace McArdle in the centre of defence for the third time this season.
Clubs need to have three players on international duty to apply to the league to have their game postponed.
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