Celtic boss Neil Lennon admits the news that Kelvin Wilson will be out for 10 weeks with a torn Achilles has come as "huge blow".
The Hoops defender picked up the injury in the Scottish Communities League Cup third-round win over Ross County in midweek and missed the 2-0 Clydesdale Bank Premier League victory over Inverness.
"It looks like anything about eight to 10 weeks," said Lennon of Wilson's lay-off. "He has a tear in his Achilles tendon."
He added: "He had the scan yesterday and the specialist said he would have to be out as long as that.
"It is a huge blow. We already have Emilio Izaguirre and Cha Du-ri out for a few weeks. It just means we have to re-jig things a little bit in defence.
"On the plus side Charlie Mulgrew has served his suspension and he will be back in contention for both games this week and he makes us better.
"Badr El-Kaddouri can't play on Thursday so we will have to make a change anyway. Gary Hooper got a leg knock and it seemed to deteriorate so he was taken off to protect him.
"We will see how he is. I am hoping it is not too serious."
Caley remained bottom of the table but boss Terry Butcher, who revealed defender David Proctor had five stitches put in a head wound which saw him substituted, praised his players.
"We had chances," said the former Rangers and England defender. "I thought we started the game very well and we put Celtic under pressure and I thought Gregory Tade was excellent throughout the whole game."
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