De La Salle, Christian Brothers College Cork, and Midleton CBS all progressed to the last four of the Harty Cup while John The Baptist CS and Thurles CBS must meet again to decide who joins them.
Two periods of extra-time failed to separate the latter pairing in Dundrum.
It finished John The Baptist Hospital 4-28, Thurles CBS 3-31 after two periods of 10 minutes and a further two periods of five minutes.
Meanwhile, Declan Hanlon was the hero for Christian Brothers College, Cork in their victory over Nenagh CBS.
Hanlon’s last-gasp goal snatched victory from the jaws of defeat for the Cork school who prevailed by 2-14 to 2-12.
They now await the winners of the aforementioned replay at the semi-final stages.
De La Salle finished with three points to spare (1-14 to 0-14) over St Colman’s.
Alan Kirwan’s first-half goal ultimately proved to be the difference between the two teams at the final whistle in Fraher Field.
They will now face Midleton CBS - who proved too strong for Our Ladys Templemore on a scoreline of 7-15 to 0-19 – at the penultimate stage.
Harty Cup semi-final line-up:
Christian Brothers College Cork v John The Baptist Hospital or Thurles CBS
De La Salle v Midleton CBS