Stephen Robinson's new look Saints suffered a demoralising 3-1 defeat of their last pre-season sport earlier than their Premier Sports activities Cup opener in opposition to Arbroath.
On the again of two robust wins in Northern Eire Stephen Robinson set his aspect up in an attacking 4-3-3 formation in opposition to English League Two aspect Northampton, with Saints followers getting their first glimpse of summer time signing Toyosi Olusanya who began on the correct wing.
Ryan Flynn anchored the midfield alongside Mark O'Hara and Ethan Erhahon, with Charles Dunne partnering Declan Gallagher at centre again.
After a sluggish begin St Mirren shocked the sport into life as Marcus Fraser picked out Alex Greive on the sting of the field with a pinpoint cross.
The New Zealand worldwide teed up Mark O'Hara who emphatically slammed into the underside nook from 20 yards.
The Buddies' lead lasted lower than ten minutes after the house defence got here unstuck from a easy nook. Mitch Pinnock's supply wasn't handled, Ben Fox finally scrambling the ball in from close-range.
Saints striker Alex Greive was wanting full of life in an unfamiliar position on the left wing, recurrently reducing inside to trigger the Northampton defence a headache as he linked up along with his fellow forwards.
Ryan Flynn and O'Hara dragged pictures vast as the primary half meandered to an in depth, with the depth dropping dramatically after the guests' equaliser.
St Mirren keeper Trevor Carson was known as into motion simply earlier than the break, denying Fox his second of the match with a wonderful cease from the midfielder's lengthy vary effort.
The Buddies made two adjustments on the break, with Jay Henderson and Scott Tanser changing Olusanya and Fraser respectively.
Carson needed to be at his finest once more to disclaim Northampton, who fielded a wholly completely different XI within the second half, beating away Danny Hylton's header to maintain the edges stage.
Jonah Ayunga blazed over the bar from the sting of the field as either side pressed for the lead.
Saints made six adjustments on the sixty minute mark, with Greg Kiltie, Dylan Reid, Kieran Offord, Peter Urminsky, Murray Campbell and Lewis Jamieson all getting into the fray.
Offord drew a wise save from Jon Maxted because the Saints' younger weapons appeared to spark the house aspect into life.
Saints sub keeper Urminsky then showcased his ability, pulling off a wonderful low save to cease Josh Tomlinson's highly effective low shot from nestling within the backside nook.
St Mirren have been determined to bag a winner to ship the house followers completely satisfied. It virtually got here when Offord swivelled cleverly on the sting of the field earlier than flashing a vicious lengthy vary effort inches previous the submit.
With simply over ten minutes to go Northampton lastly discovered a decisive second purpose. Some woeful defending from Saints' makeshift backline allowed Hylton to jab dwelling from shut vary.
Issues went from dangerous to worse for Robinson's aspect as Hylton made no mistake from the penalty spot to take the end result away from the Buddies.
St Mirren: Carson (Urminsky 60), Fraser (Tanser 45), Gallagher (Shaughnessy 73), Dunne (Campbell 60), Tait, Flynn (Taylor 73), O'Hara (Kiltie 60), Erhahon (Reid 60), Olusanya (Henderson 45), Greive (Offord 60), Ayunga (Jamieson 60).
Subs not used: Pressure.