Livingston boss David Martindale admitted his side’s defending cost them points in Paisley.
The home side netted a dramatic 90th minute winner despite being reduced to 10 men - and having conceded an equaliser to the Lions just four minutes earlier.
An otherwise drab affair suddenly burst into life in the final stages. Keanu Baccus had nodded the Buddies in front midway through the second-half before Jonah Ayunga saw red on 76 minutes for handball after blocking a goalbound Scott Pittman strike.
Livi were unable to take advantage of the opportunity as Sean Kelly blasted high over the bar but they were able to draw level with four minutes left on the clock as substitute Bruce Anderson ghosted beyond his man to turn home a wonderful Joel Nouble cross.
Strangely, though, it was Stephen Robinson’s men who controlled the final moments.
Shamal George appeared to have rescued a point for the away side with a wonderful save to tip Scott Tanser’s free-kick over the bar only for Alex Grieve to pop up moments later as slam the ball beyond the keeper after Livi failed to deal with a corner-kick.
A dejected Martindale admitted their inability to defend their box was, ultimately, what cost them travelling back across the M8 with something to show for their efforts.
He commented: “If you want something to sum the game up, they defended their box better than us. That’s really what it all comes down to.
“First goal, we all turn our back on the throw. I don’t know if they are waiting on the long one into the box.
“St Mirren only have three or four players in the box at that point and we have seven or eight. That’s got to be dealt with better but we have to lock onto our shape.
“It’s a good ball and a good finish but we have to do better and can’t allow cheap balls into our box.”
He added: “You get the penalty and one of the best technical players in the team doesn’t hit the target, so that’s disappointing.
“With striking a ball, Sean is one of, if not the, best player at the club.
“But we managed to get ourselves back in the game. Wee Bruce’s finish is fantastic and then I think we needed to be more aggressive after that.
“We allowed them easy possession in our half. Then it’s a free-kick tipped over the bar, two corners and we have plenty of numbers in the box and don’t deal with it. We shot ourselves in the foot.”
Don't miss the latest news from the West Lothian Courier. Sign up to our free newsletter here
