Neil Lennon revealed skipper Scott Brown will see a specialist to ascertain whether or not he is to go under the knife.
The midfielder sat out Celtic’s 6-2 Clydesdale Bank Premier League home win over Dundee United at the weekend with an abductor problem and will miss the trip to St Johnstone tomorrow night.
Brown, however, has been bothered by an on-going hip problem this season which was thought at one time to require surgery, but both problems are to be addressed.
Hoops manager Lennon said: “Scott will be seeing a specialist regarding his abductor and we will wait on the outcome of that.
“We will have a look at what he had before and he might require surgery, we are not sure yet, we will see what the specialist says but hopefully that won’t be the case.”
Meanwhile, Skipper Scott Brown and defender Mikael Lustig will be missing again for Celtic’s Clydesdale Bank Premier League game against St Johnstone at McDiarmid Park tomorrow night.
Brown will see a specialist about his abductor problem while Lustig is out with a thigh injury.
Greece striker Georgios Samaras is back in training after recovering from a hamstring injury but he is not yet ready.
Provisional squad: Forster, Matthews, Wilson, Rogne, Mulgrew, Ambrose, Izaguirre, Forrest, Kayal, Ledley, Wanyama, Rogic, Stokes, Watt, Miku, Lassad, Zaluska, McGeouch, Chalmers.