Rangers will be without summer signing Nikica Jelavic for a 'number' of matches as he requires an ankle operation.
The Croatian striker sustained the damage in a tackle with Hearts' Ian Black in the second half of a 2-1 win at Tynecastle.
Jelavic now needs to go under the knife and Rangers expect him to be sidelined for a number of weeks.
The former Rapid Vienna striker has made a good impression in the SPL with two goals in five league appearances for the champions.
"Following a tackle in Saturday's game against Hearts at Tynecastle, Nikica Jelavic suffered ankle ligament damage that requires surgery," read a club statement.
"The striker will now miss a number of matches for the club."