Scotland manager Gordon Strachan's plans for Friday's game against Croatia have been dealt another blow after Brighton defender Gordon Greer did not travel with the squad.Greer has been struggling with tonsillitis ahead of the trip to Zagreb for Friday's World Cup qualifier. That makes seven call-offs after Scott Brown, James Forrest, Danny Fox, Lee Wallace, Gary Caldwell and Liam Bridcutt were all forced to pull out. Grant Hanley went over on his ankle in training earlier in the week, but has declared himself fit.With Brown and Caldwell out, and Darren Fletcher and Kenny Miller absent from the squad, there had been a question mark over who will wear the captain's armband. by James Morrison will be the man of the moment for the game. Speaking before the announcement coach Mark McGhee said: "Gordon knows who is going to captain the team and he actually invited me this morning to tell you that. But I felt very strongly that that's something that should be reserved for the manager. It's such an important thing. There are moments in any manager's reign that are significant and naming the captain is one of them. So I declined that opportunity and told him he's got to do it himself."Despite having no chance of qualification, McGhee insists there is plenty to play for against a side that sits joint top of the group. He said: "Their position in the standings is impressive and makes them formidable opposition. But I wouldn't say we have nothing to lose. People are in the squad, some because they are going to be in future squads, others have an opportunity because of other circumstances and have a chance to prove to the manager they should be in future squads. There is a lot to play for. They have an opportunity to prove they should be here and stamp that for the future."