McCombe was signed on loan by Brown and had started to form a partnership with Morgan conceding only two goals in five games whilst also scoring in the JPT clash.
His loan spell was expected to end on 2 January 2012 in any event so Preston will now have to find an alternative centre back for the festive games at home to Carlisle and Sheffiel Wednesday.
Alexander and Unsworth will also have to find a new left back for the Boxing Day clash as Steven Smith is suspended after picking up five yellow cards this season.