Two second half goals saw Glentoran defeat Glenavon at the BetMcLean Oval and book their place in the European play-offs final.
The Glens will host Larne in the decider for a place in the UEFA Conference League on Friday night, kick-off 7:45pm.
Glentoran had an early effort on target after Seanan Clucas received the ball from the left and tested keeper Josh Clarke who responded with a good reflex save.
However the remainder of the first half failed to produce any chances of note, although Glentoran did have penalty appeals waved away after claims that a Conor McMenamin attempt struck the hand of Calum Birney.
But the deadlock was broken just three minutes after the break. Jay Donnelly created the opening with a pass to McMenamin who demonstrated his skill by dinking the ball over Clarke and into the net.
Conor McCloskey came close to levelling for Glenavon a little later with a right-foot effort following a run down the left but his shot flew just wide.
Glentoran made sure of their place in Friday's final, however, when Donnelly made it 2-0 on 72 minutes with a well directed header after McMenamin turned provider with a perfectly delivered left-wing cross.
Glentoran: McCarey, Kane, Burns, Marshall, J. Donnelly, McClean, Clucas, McMenamin, Cushnie, Plum, Cole subs McCartan, R. Donnelly, O'Connor, Crowe, Powers, Jenkins, Glendinning
Glenavon: Clarke, Birney, Haughey, O'Connor, Campbell, Snoddy, McCloskey, Fitzpatrick, Wallace, Singleton, Ward subs A. Doyle, Scannell, O'Mahony, Doran, J. Doyle, Garrett, Hamilton