The Saints came marching into New Broomfield and promptly left some three hours later with their tails between their legs.
Airdrie, now with six games unbeaten under their belt, are playing with confidence and self belief. It's a belief that is quite justified given their recent results against the top teams.
However, today they almost fell behind after three minutes. Only a brilliant save by keeper Stephen Robertson kept the score-sheet blank after Jason Scotland had carved out an opening for Ryan Stevenson.
Saints did open the scoring in the 19th minute. Simon Mensing had tried to chip the ball over Stephen McKeown, but the Airdrie man stuck out a hand and conceded a penalty in so doing. Paul Sheerin took the kick and that was 1-0.
Three minutes Kevin Rutkiewicz cleared the ball off his own line before fouling Bryan Prunty in the box. Another penalty, another clean strike, this time McKeown turned from sinner to saint in converting the spot-kick.
Airdrie's determination to win was apparent as was Saints' crumbling confidence.
After 35 minutes Airdrie scored their second and, as it turned out, the winner. Prunty raced into the box before being tackled by Goran Stanic. Stanic won the ball but it broke kindly for Airdrie and spun into the path of Willie McLaren. Taking his time to pick his spot, McLaren finally drilled the ball past the helpless Kevin Cuthbert.
The second half was one of containment which the home side did particularly well. In the last minute another rash challenge by Mensing earned him his second yellow of the afternoon and an early bath.