St Mirren end Celtic's three year record
Denny Johnstone and Bahrudin Atajic scored for the visitors but some sloppy defending allowed Thomas Reilly and substitutes Kieran Doran and Jack Smith to give St Mirren full points.
The last time that Celtic tasted defeat on the road at this level was in a 2-1 defeat against Dundee United at St Andrews in October 2009.
With the development side facing Blackburn Rovers on Thursday it was a very youthful looking Celtic side with only Patrik Twardzik and Atajic over 18 years of age while St Mirren were able to call upon David Barron, Graham Carey and goalkeeper Chris Smith.
The first chance of the game fell to Johnstone in the ninth minute when he raced onto a pass out of midfield from Connor McManus but after nudging the ball around goalkeeper Smith he was unable to direct his shot into the net from a tight angle.
Two minutes later Johnstone did find the net with a glancing header at the front post from a perfectly weighted Twardzik cross from the left.
Celtic should have kicked on from going in front but found the scores levelled in the 35th minute when Thomas Reilly shot home from 15 yards following a good passing move from the home side.
St Mirren started the second half in confident fashion, deservedly going in front in the 62nd minute when substitute Doran headed home unchallenged from a corner.
The Saints looked like extending their lead but shortly after Paul McMullan had saw a shot strike the post Atajic levelled the scores with an 18 yard shot that took a deflection to spin over Smith into the net.
The game could have gone either way but seven minutes from the end Liam Henderson and Stuart Findlay were caught in possession with Jack Smith drilling the decisive goal low past Daniels.
ST MIRREN: Smith, Meechan, Yaqub, Hu,ghes, Barron, Kelly, Brown, Carey, Reilly, Fulton, McLear
SUBS: Hughes, Scullion, Coyle, Smith, Brady, Doran, Williams
Daniels: O’Connell, McNally, Findlay, McManus: Johnstone, Kidd, Lindsay, P Twardzik: Atajic, McMullan
SUBS: Fasan, Eadie, Kelleher, Donnelly, Henderson, Kirwan, McDonagh
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