Brechin City made a mockery of Airdrie's fine defensive record as they ran out convincing winners.
David White volleyed the ball past Airdrie goalkeeper Stephen Robertson, but Stuart Noble latched on to a fine cross from Allan Russell to level.
Russell slotted home to put Airdrie ahead five minutes after the break.
But Stuart Callaghan' curling free-kick levelled matters again, Calum Smith rounded the goalkeeper to score then Charlie King ran through to fire home.
Brechin: Craig Nelson, Richard Walker, Stuart Callaghan, White, Murie, Fusco, Byers, Adam Nelson, Calum Smith (Gribben 86), King, Darren Smith.
Subs Not Used: Ward, Janczyk, Dyer, McCluskey.
Booked: Adam Nelson, Byers, Stuart Callaghan.
Goals: White 21, Stuart Callaghan 66, Calum Smith 68, King 80.
Airdrie Utd: Robertson, McKenna, Lovering (Watt 81), McDonald, Smyth, Donnelly, McDougall, McKeown, Russell, Noble (Prunty 71), Waddle (Gillies 76).
Subs Not Used: Jenkins, Hollis.
Booked: McDonald, Lovering.
Goals: Noble 33, Russell 50.
Ref: E Norris