Danny Griffin's debut will be delayed a further week and he will turn out for the Under-21s at McDiarmid Park on Monday.
It had been hoped that the ex-McDiarmid Park man would be involved against Saints' first team on Saturday and expectations that he would finally make his United debut were heightened when he played nine minutes of Northern Ireland's friendly against Yugoslavia on Wednesday night.
The delay continues to be disappointing for all concerned but Wednesday's brief international appearance means Danny has joined Pat Onstad as the only United players ever to have been capped for their country before playing for the Club.