Match ends, Motherwell 0, St. Mirren 1.
St Mirren secured only their third Scottish Premiership win of the season, beating Motherwell to move three points clear of bottom side Dundee.
Simeon Jackson got the vital goal - a rebound shot after goalkeeper Mark Gillespie had denied Cammy Smith.
Motherwell had earlier come close to a breakthrough when Curtis Main headed into the hands of Dean Lyness.
And Main and David Turnbull had efforts saved by Lyness as the hosts' day ended in frustration.
Both sides are at home for their penultimate games of 2018 on Wednesday, with St Mirren hosting St Johnstone and Kilmarnock travelling to face Motherwell.
And with just a two-point gap between themselves and Hamilton Academical, the Buddies could get out of the bottom two before the winter break.
St Mirren dig in for victory
A midweek defeat at Celtic Park had taken the wind out of Motherwell's sails and the hosts were without their manager in the dugout as Stephen Robinson started a touchline ban.
St Mirren had lost at home to Aberdeen last time out but knew, with Dundee visiting league leaders Celtic, that anything gained in Lanarkshire could give them a cushion before Christmas.
The hosts were the more forceful side in a poor first half but too often lacked accuracy at the vital moment. Allan Campbell lofted a cross on to the head of Main but the striker's tame effort proved an easy catch for Lyness.
Lee Hodson curled an effort over the crossbar in one of St Mirren's rare forays forward before the break and Jackson could not get a hold of his shot when presented with a chance early in the second period.
St Mirren manager Oran Kearney sent on top scorer Adam Hammill then Smith and the substitutes gave the visitors the attacking impetus they needed.
Smith got in behind Motherwell substitute Gael Bigirimana to force a save from Gillespie and Jackson was on hand to bury the loose ball.
Main's downward header was blocked by the legs of Lyness and Turnbull's swerving long-range shot and late header were also repelled by the keeper while Hammill tested Gillespie at the other end.

'Ferdinand immense for St Mirren' - analysis
BBC Scotland's John Barnes at Fir Park
The first half lacked any festive cheer, with composure, creativity and chances in short supply. A sprinkling of fairy dust would have been required to make it sparkle.
David Turnbull showed most urgency for Motherwell with some neat skills, but when he did provide deliveries into the opposition box they found Anton Ferdinand in commanding form.
The experienced Englishman was immense at the heart of the St Mirren defence and you can understand why other clubs have been monitoring his recent performances. He virtually strolled through the game with a tidy simple approach and a lesson in the art of defending.
If St Mirren were to lose him in January, it would be a blow to their survival aspirations. However their first away win of the season will have given them renewed belief.
'Motherwell too slow' - reaction
Motherwell assistant manager Keith Lasley: "Everything was too slow, too precise. We never started and that set the tone throughout. I don't think we deserved to win.
"The next game becomes even bigger now, against Kilmarnock on Wednesday. We've got to show more. We demand a reaction."
St Mirren manager Oran Kearney: "A lot of questions have been asked this year from outside the dressing room. I think we've asked a lot questions inside the dressing room and today we got more of the answers that we wanted to get.
"Simeon's bright and he knows where the net is. It's nice to see him get his goal. Dean Lyness had to weigh in with two or three big saves. Anton Ferdinand's been brilliant."
Line-ups
Motherwell
Formation 3-1-4-2
- 20Gillespie
- 5Aldred
- 21MbuluSubstituted forBigirimanaat 61'minutes
- 18Dunne
- 4McHugh
- 14GrimshawBooked at 12mins
- 8CampbellSubstituted forSammonat 81'minutes
- 28Turnbull
- 2TaitSubstituted forBowmanat 81'minutes
- 9Main
- 24Johnson
Substitutes
- 3Taylor-Sinclair
- 11Frear
- 12Bowman
- 13Ferguson
- 17Bigirimana
- 19Sammon
- 23Gorrin
St Mirren
Formation 3-1-4-2
- 26Lyness
- 19Jones
- 35Ferdinand
- 15Baird
- 4McGinn
- 21Hodson
- 2McGinn
- 27EdwardsSubstituted forSmithat 59'minutes
- 39Erhahon
- 20CookeSubstituted forHammillat 56'minutes
- 11JacksonSubstituted forFlynnat 88'minutes
Substitutes
- 8Flynn
- 10Smith
- 14Kirkpatrick
- 16McShane
- 25Rogers
- 40Breadner
- 77Hammill
- Referee:
- Don Robertson
- Attendance:
- 4,540
Match Stats
- Possession
- Home47%
- Away53%
- Shots
- Home4
- Away3
- Shots on Target
- Home2
- Away2
- Corners
- Home9
- Away5
- Fouls
- Home11
- Away6
Live Text
Post update
Full Time
Second Half ends, Motherwell 0, St. Mirren 1.
Post update
Corner, Motherwell. Conceded by Jack Baird.
Post update
Foul by Liam Grimshaw (Motherwell).
Post update
Ethan Erhahon (St. Mirren) wins a free kick on the right wing.
Post update
Corner, St. Mirren. Conceded by Carl McHugh.
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Corner, St. Mirren. Conceded by Mark Gillespie.
Post update
Attempt saved. Adam Hammill (St. Mirren) right footed shot from the right side of the box is saved in the centre of the goal.
Substitution
Substitution, St. Mirren. Ryan Flynn replaces Simeon Jackson.
Post update
Gael Bigirimana (Motherwell) wins a free kick in the defensive half.
Post update
Foul by Cameron Smith (St. Mirren).
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Corner, Motherwell. Conceded by Jack Baird.
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Foul by Tom Aldred (Motherwell).
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Alfie Jones (St. Mirren) wins a free kick in the attacking half.
Post update
Corner, Motherwell. Conceded by Jack Baird.
Substitution
Substitution, Motherwell. Ryan Bowman replaces Richard Tait.
Substitution
Substitution, Motherwell. Conor Sammon replaces Allan Campbell.
Post update
Foul by David Turnbull (Motherwell).
Post update
Ethan Erhahon (St. Mirren) wins a free kick in the defensive half.
Post update
Attempt saved. Danny Johnson (Motherwell) header from the centre of the box is saved in the centre of the goal.