Wheater made three substitute appearances before the recent international break having returned from a long-term knee injury but will now be laid low by a calf strain for three weeks.
Wanderers boss Dougie Freedman has full-back Sam Ricketts and forward Craig Davies available once more.
The Welsh duo sat out Tuesday night's 1-0 win over Huddersfield at the Reebok having received red cards during the second half of the 3-2 loss at Charlton last weekend.
Along with Davies' return, Freedman's attacking options are further boosted by Robert Hall after the on-loan West Ham youngster completed a successful week of training.
Midfielders Keith Andrews (Achilles) and Mark Davies (knee) remain on the sidelines alongside right-back Tyrone Mears (illness).