Ross County narrowed the gap between them and St Mirren to a single point after a convincing win in Paisley.
Richard Brittain's free-kick strike opened the scoring for County, but Steven Thompson levelled in 50 minutes.
However, two goals from Sam Morrow and a brace from Ivan Sproule on his debut brought victory to the Highland side as the St Mirren defence imploded.
Lewis Guy failed to grab a consolation for the home side when Mark Brown saved his last-minute penalty.
The first Scottish Premier League match after the winter break promised goals as the last time these sides met at St Mirren Park they served up a nine-goal thriller
Both sides knew a win could give them a crucial edge as they looked to climb the table, with St Mirren four points clear of County going into the match - though the visitors have two games in hand.
The game started in an open fashion, Grant Munro and Thompson both passing up early chances at either end of the pitch.
A neat interchange on the edge of the St Mirren box let in Ross County debutant Sproule, who shot at the legs of Craig Samson, with Rocco Quinn in a better position.
A goal seemed inevitable, and it came from the boot of County captain Brittain, who has signed a pre-contract with St Johnstone.
His free-kick from 25 yards flew into the top-right corner of the net, with Samson left stranded - Brittain's sixth goal of the season.
County were dominating possession in midfield, and Brittain played in Sproule in the inside-right channel, and his powerful right-footed shot fizzed just past the post.
St Mirren were struggling to create as the half went on, with Thompson cutting a frustrated figure as a series of offside decisions and a penalty claim went against him.
However, manager Danny Lennon brought on Dougie Imrie for Newton at half-time, and five minutes later the Buddies were level.
David Barron played the ball into the box, where Thompson spun and hammered the ball past Brown from 14 yards.
It was the home side's turn to enjoy a spell of dominance in possession, but they toiled to carve out any clear opportunities.
After the hour mark the game began to stretch after a scrappy phase, and Sproule was unfortunate with a low effort from a tight angle which flashed narrowly wide.
This was a precursor to a torrid 15 minutes where the St Mirren defence collapsed and conceded three goals which killed the match.
But, moments later, a back-header from Barron fell short, allowing substitute Sam Morrow to dart in and slot the ball low past Samson.
St Mirren looked shell-shocked at this and Vigurs nicked the ball off Jon Robertson from a St Mirren throw, and his toe poke fell into the path of Sproule, who rifled the ball home.
Then, Quinn fired in a low effort from the edge of the box, which Samson could only parry into the path of Sproule, six yards out, who knocked the ball into the empty net.
Guy went down in the box at the death, with referee Euan Norris pointing to the spot, but even this consolation was denied them as his low penalty was saved by Brown.