Eamon Power and Michael Jones pointed inside the last five minutes in Ballyhale to send Scoil Aireagail through to the semi-finals.
Offaly's Colaiste Naomh Cormac were never in front, but a 53rd-minute point from a free by Dillon Murray put them within striking distance during a hard-fought second half. However, they were hit for two late scores, which put the Kilkenny side through for a meeting with Borris VS.
Scoil Aireagail started well, with points from Colm Phelan and Ronan Corcoran (two) helping them find their feet.
Naomh Cormac opened their account in the 15th minute through Dillon Murray, the only player from his side to point before the break. A 25th-minute goal from Andy Fitzpatrick was the main difference between the teams as Scoil Aireagail led by 1-4 to 0-3 at half-time.
The Offaly lads chased hard after the turnaround and an early goal from Dan Mahon gave them great heart. They never got closer than two points, however, and the Ballyhale boys were relieved to hear the final whistle.
SCORERS – Scoil Aireagail: R Corcoran 0-5 (3f), A Fitzpatriack 1-0, P Delaney, M Jones, C Phelan, E Power 0-1 each. Col Naomh Cormac: D Murray 0-4 (4f), D Mahon 1-0, C Kiely 0-1.
SCOIL AIREAGAIL – A Roche; J Kenneally, E Aylward, D Halligan; P Kirwan, J Grace, A Doherty; P Delaney, B Phelan; M Jones, C Phelan, R Corcoran; K Farrell, A Fitzpatrick, R Coffey. Subs: E Power for K Fennnelly, D Doran for Coffey.
COL NAOMH CORMAC – C Kiely; K Ryan, O Mahon, A Kilmartin; D Young, J Kilmartin, S Lowry; S Guinan, A Spain; D Mahon, D Murray, P Troy; C Dooley, H Dazell, C Gath. Sub: K Bracken for Dooley.
Ref – J Bennett (Kilkenny).