Elliot Poole's stoppage-time goal sent St Brelade into their first Trinity Shield final for three years as they beat St Clement 3-2.
Carl Hinds had put St Clement ahead early on before Poole struck an equaliser after 10 minutes.
Hinds made it 2-1 on 44 minutes but Fraser Barlow equalised for a second time in first-half stoppage time.
Meanwhile, St Saviour are through to the semi-finals after beating St Lawrence 3-2 on penalties.
|Recent Trinity Shield winners|
|2013: St Lawrence|
|2012: St Ouen|
|2011: St Lawrence|
|2010: St Saviour|
St Lawrence, the 2013 champions, scored three goals in the last 17 minutes to force extra time having been 3-0 down.
But they had Ben Gallichan and Tommy Buchanan sent off in extra time and could not force a winner.
St Saviour will now face reigning champions Grouville in the semi-finals in Monday.