Glentoran stunned Glenavon at Mourneview Park to set up a play-off shoot-out with Cliftonville for the Irish League's final Europa League spot.
Darren Murray's brace set up a 4-2 win for Mick McDermott's men that sees them travel to Solitude on Saturday to face the Reds, who needed extra-time to eventually beat Coleraine 5-3.
It will be a rematch of last year's final, when Cliftonville were victorious, but this time around the Glens look to be in good form.
They are still unbeaten since new boss McDermott took over and against the Lurgan Blues they were cool, calm and composed in reaching the final.
Murray had given them the lead in the first half with a fine strike before Caolan Marron sent the sides in level at half-time with a raking 35-yard effort.
Curtis Allen followed that up with a fine strike of his own early in the second half to put the Glens back ahead, only for Andy Mitchell to curl in a free kick for Glenavon.
But Robbie McDaid instantly put the visitors back ahead when he capitalised on a defensive error, with Murray's second making sure of the win late on.
At Solitude in the other semi-final, James McLaughlin's hat-trick looked to have Coleraine into the decider, the striker completing his treble with a fine overhead kick early in the second half.
Reds hitman Joe Gormley had scored just before the interval, with Conor McMenamin pulling a further goal back midway through the second half.
Then, deep into injury time, Ryan Curran was fouled by Josh Carson in the box to give away the spot kick, which the striker calmly slotted past 'keeper Chris Johns.
In extra time, the hosts seemed to have the stronger legs and it told when they forged ahead through Levi Ives, with McMenamin wrapping it up in the dying stages.