St Johnstone boss Steve Lomas has been dealt a blow with the conformation that defender David McCracken has fractured a cheek bone.
The centre-half sustained the injury after clashing heads with Celtic midfielder Victor Wanyama after only five minutes of Sunday's 1-1 draw in Glasgow.
Further diagnosis of the injury will take place later today and the 31-year-old is likely to miss up to six weeks of football and may require surgery.
McCracken was only recalled to the starting line-up in place of Steven Anderson for the Celtic Park encounter.
Meanwhile, Lomas is facing a minimum two-match touchline ban after falling foul of referee Iain Brines during the game with the Hoops.
The case against Lomas will be heard by the SFA Judicial Panel later this month.