Brechin continued their remarkable run since being relegated earlier this month as they grabbed their fifth point in four games, and it could easily have been better for City who led three times in a thrilling end-of-season encounter.
The opening minutes were totally one sided with Airdrie's William McLaren forcing a terrific save at full stretch from John Hillcoat and then setting up Gary Twigg and Bryan Prunty, who both shot fractionally wide.
But Brechin then took a shock lead in their first serious attack when a hopeful high ball caused confusion in the home penalty box, and Scott Devlin controlled the bouncing ball before turning and firing a low shot into the corner of the net.
Deep into injury time at the end of the first half Prunty nodded home his 15th goal of the season after Stuart Taylor's header had been blocked.
Brechin were back in front early into the second period when a mix-up between Allan McManus and goal-keeper Stephen Robertson left Devlin with a simple tap-in.
Brian McPhee came off the bench for Airdrie, and within 30 seconds of his arrival the veteran forward has equalised with a perfectly-judged righ-foot effort.
Another terrible blunder by Robertson allowed Kevin Byers to chip the ball into the unguarded net from fully 45 yards as City moved ahead for the third time.
Substitute Chris Templeman almost made it 4-2 moments later, but Airdrie salvaged a well-deserved point with 12 minutes left thanks to a close-range header from defender Neil McGowan, his first goal in 140 appearances for the club.
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