St Mary's are waiting on the all-clear for their Leinster U18 Schools captain Liam Curran ahead of their semi-final with Clongowes Wood.
The influential second-row retired injured with a blow to the head in the first half of the quarter-final win over Cistercian Roscrea last week.
It would seem as though the odds are slightly against Curran making a full recovery, as coach Rodney O'Donnell admitted he will have to wait until "just before the match" to make a final decision.
If Curran does not make it, Paddy Doran, the boy who replaced him in the 23rd minute of the quarter-final, is in prime position to partner Jerry Sexton in the engine room.
The wily O'Donnell was quick to laud the strength of Clongowes for the semi-final: "They must be odds-on favourites at the moment," he said. "We're only making up the numbers, according to the bookies. Of the four left in the competition, we are the outsiders."
Well, not exactly.
PADDY POWER BETTING: St Michael's 1/1, Clongowes Wood 6/4, St Mary's 6/1, St Gerard's 8/1.
Ballymena threaten Methodist supremacy
It would appear the Ulster Schools Senior Cup is shaping up quite nicely with Methodist not altogether the odds-on proposition they have been for the past few years.
It would appear the greatest threat to their domination up North seems to come from Ballymena Academy, who are drawn at home to Stephen Ferris's Friends School from Lisburn in the quarter-final this Saturday, following their 22-3 dismissal of Limavady Grammar.
Ulster U19 Schools lock David Whann is their pack leader and they have a jewel of a player in Ireland U18 Schools full-back Charlie Simpson.
Methodist have also earned a home tie against Portora Royal's conquerors (15-12) Ballyclare High. The champions were given a fright by a well-drilled Royal Armagh (13-6) in the last 16. They will look to Ireland U19 Schools half-backs Blane McIlroy and Paddy Jackson for control.
The surprise package of the competition are Dalriada. They accounted for Campbell (15-5) with a remarkable defensive performance that reflected their unity of purpose to earn an away date at BRA. The Royal Academy required a second shot to knock out RBAI (18-16) in a replay. They will be battle-hardened.
Wallace High are also considered a dangerous unit for the manner in which they humbled Omagh Academy (24-0). They will have home advantage over Regent House, 23-11 winners against Coleraine AI, on Saturday.