Airdrieonians will meet Morton in the Championship play-off final next Tuesday and Friday after two dramatic semi-finals.
Airdrie looked to be heading out against Cove Rangers when Rory McAllister put the visitors 2-1 ahead in stoppage time but Jack McKay equalised right at the end. Calum Gallagher made it 3-2 on the night and 4-3 on aggregate with the deciding goal after 108 minutes.
Craig McGuffie scored in the last minute of extra time as Morton overturned a 2-1 first-leg deficit with a 3-1 victory over Montrose at Cappielow.
In the League 1 semi-finals, Dumbarton beat Stranraer 1-0 at the C & G Systems Stadium after a 0-0 draw on Saturday and a 2-2 draw was enough to take Edinburgh City past Elgin City, following Edinburgh's 1-0 triumph at Borough Briggs in the first leg.
PLAY-OFF FINAL DATES CONFIRMED, WITH ALL FOUR TIES LIVE ON BBC ALBA
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