Celtic striker Giorgos Giakoumakis has been ruled out of Sunday's Scottish Cup semi-final against Rangers.
Ange Postecoglou confirmed at his Friday press conference that the forward had not recovered from a hamstring injury in time to feature at Hampden.
But David Turnbull, who was a fitness concern earlier this week, is fit and available.
Celtic head to the national stadium chasing a domestic Treble but must now do so without their in-form Greek star.
The loss of Giakoumakis has been softened by the return of Kyogo Furuhashi - but Postecoglou said after last weekend's thumping win over St Johnstone that he was unlikely to start.
And he admitted on Friday that he does not believe the forward is ready to complete 90 minutes.
A second-half sub's appearance was the Japanese star's first outing since aggravating a hamstring problem at McDiarmid Park on Boxing Day.
Postecoglou could now draft Daizen Maeda, who has become a firm fans' favourite in recent weeks, into the central striking role.
