Steve Clarke admits Rangers star Ryan Jack is irreplaceable in the Scotland midfield.
The 29-year-old was named in Clarke 's squad for games against Austria, Israel and the Faroe Islands despite a calf knock.
Jack has not made an appearance for his club in over a month and soon pulled out of the squad.
Clarke is expected to give the likes of Kenny McLean, John Fleck or Scott McTominay the chance to step into the hole left in the centre of the park by Jack.
However, he admits there isn't anyone in the squad who can fill the position Jack plays for the national side.
Clarke said: "We lost Ryan Jack but we sort of pre-empted that so we are in good shape.
"It is a blow for us because he has done well for us and he plays a certain position in midfield that without him we don't really have.
"So we will miss him but we have got a really good squad now so time for someone else to step forward.
"The little time we have had on the training pitch has been really good work, high quality so hopefully we can take that on to the pitch. In my head, I know the team."
Jack has missed Rangers ' Europa League games against Royal Antwerp, Slavia Prague and the derby day draw with Celtic.
His last appearance for the Ibrox side came in the 4-1 win over Dundee United in mid-February.
