Connor Ronan's sublime finish gave St Mirren's top six hopes a serious shot in the arm.
The Buddies went into tonight's clash at the SMISA Stadium knowing a win over the Dons would see them claw themselves to within three points of their sixth-place opponents.
The first half was a non-event, with the Saints sitting in deep to frustrate the life out of a uninspiring Aberdeen side who struggled to break through the defence of the stubborn hosts.
And that defensive quality paid dividends when Ronan produced the one piece of quality of the entire night, picking up the ball on the edge of the box on the hour mark before cutting in and slamming into the far corner past a sprawling Joe Lewis.
And the Buddies easily held firm to keep up their 100 per cent winning record since returning from the winter break, with the three points lifting them to joint-seventh in the Premiership table - just three points behind the Dons.
Jamie McGrath was surprisingly restored straight into the Saints starting XI having held clear-the-air talks with Jim Goodwin on Monday, with the Ireland international deployed in an unfamiliar left wing role.
Alan Power came back into the heart of the midfield, with Eamonn Brophy also back to lead the line after both were rested in the club's 2-1 Scottish Cup victory over Ayr United three days earlier.
The Buddies went into the game buoyed by two successive wins and almost took an early lead when teenager Jay Henderson's half-volley flew over the bar.
Marcus Fraser then saw a glancing header drift wide of the left-hand post as the hosts exerted some early pressure on the Dons.
Scott Brown breathed a sigh of relief when his sclaffed clearance went unpunished by Greg Kiltie, who fired well wide from a promising position.
The home side were pressing much less than usual early on, content to let the visitors keep the ball in their own half.
The game meandered at a pedestrian pace in the opening half an hour, with the Dons almost shocking it to life when Lewis Ferguson slammed just inches wide with Saints keeper Jak Alnwick looking unlikely to reach it had it crept inside the post.
St Mirren were frustrating the life out of Aberdeen, with Lewis Ferguson blasting over the bar from distance as the visitors continued to struggle to break through the defence.
While working well at the back, the Buddies were offering little to no threat at the other end, with Joe Lewis a virtual bystander in the opening 45 minutes.
Alnwick had to be alert to tip a Calvin Ramsay cross over the bar just before the break, with both sides looking devoid of ideas heading into the break.
Aberdeen started the second half brightly, with a neat move on the right wing teeing up Brown on the edge of the box. He curled over the bar as the visitors looked to assert themselves on the match.
Charles Dunne almost shot himself in the foot when he headed a Ryan Hedges cross out of Alnwick's hands, with teammate Scott Tanser coming to the rescue to block Brown's low shot on the line.
Christian Ramirez then blasted well wide from a corner as the Dons continued to pen the Buddies into their own half.
Referee Grant Irvine was on the end of a torrent of boos from the Saints crowd after Teddy Jenks appeared to handle on the ground as the home side looked set to break up the pitch, with the man in black guilty of more than a few questionable decisions throughout the match.
With an hour played the Buddies had hardly troubled Lewis. But the Dons stopper was soon picking the ball out of the back of his net when, after a Brophy cross dribbled all the way across the box, Ronan was there to collect before skinning Ramsay and curling an unstoppable shot into the far corner to break the deadlock.
The Saints handed a home debut to recent addition Alex Greive, who replaced a tiring Brophy with 20 minutes left on the clock.
The New Zealander almost made the perfect impression when he broke forward well into the Dons box, with only a well-timed tackle stopping him from getting his shot away.
While many in the stands expected an Aberdeen onslaught having gone behind, the response was remarkably underwhelming.
The Buddies were hardly troubled in the closing stages, with Jim Goodwin clearly more than happy with the winning response of his team after a disappointing spell at the end of 2021.
