Scans have revealed that the centre back has strained knee ligaments and although the injury is not as bad has was first feared he will be out for up to three weeks.
"Short has had a scan which revealed no damage, but he has tweaked his medial ligament, so he'll be out for two to three weeks," manager Mark Hughes told the clubs official website.
"It is a blow to lose him so early in the season, but thankfully it isn't a serious injury."