Rangers midfielder Vladimir Weiss has been all but ruled out of the Scottish Cup fifth-round replay against Celtic.
The on-loan Manchester City player suffered an ankle injury against St Johnstone on Sunday and is a major doubt, although an X-ray showed no fracture.
Steven Naismith (hamstring) and Jamie Ness (groin) remain out along with long-term absentees Kirk Broadfoot (foot) and Lee McCulloch (knee).
Source: PA