Juniors Banks o' Dee claimed their third Highland League scalp of the competition after beating Turriff United in extra-time at The Haughs, thanks to a winner from former Cove striker Jamie Watt.
Turriff were without Robbie Allan and James Chalmers from Saturday's defeat at Keith, so Leszek Nowosielski and Antonio Vastano took their places in the home midfield. Banks o' Dee started with former Highland League stalwarts Jamie Watt and Jamie Lennox in attack.
The visitors went in front in the eight minute when Jamie Lennox was brought down by Kevin Main in the penalty area, before dusting himself down and converting from the spot.
Turriff equalised on the half hour mark, Vastano's corner from the right headed firmly into the net by Ally Mackenzie to draw the home side level.
Dean Still replaced Andrzej Kleczkowski up front at half time for the home side, but it was Banks o' Dee who had a great chance to regain the lead in the 62nd minute, when they were awarded another penalty kick by referee Liam Duncan. Home goalkeeper Main emulated the penalty heroics at The Haughs on Saturday by diving low to his right to deny Lennox his second goal from the spot.
Chances came and went for both sides, but it remained all-square after 90 minutes and the tie went into extra time.
Banks o' Dee went back into the lead in the 92nd minute when Jamie Watt fired home a rebound from another Main save, despite the efforts of Cammy Bowden on the line.
Liam Strachan came on for Vastano and local youngster Scott Moir replaced Nowosielski as Turriff looked for a way back into the match, but the visitors held on for a hard-fought victory.
Dee now go on to face Inverurie Locos in the final, after they beat Huntly in the other semi-final at Harlaw Park.