Danny Racchi's superb late chip earned Kilmarnock a hard-earned comeback victory over in-form St Mirren.
Mark McAusland fired against the bar as the Buddies dominated early on and Lee Mair headed the visitors into a deserved lead after 10 minutes.
But, after boss Kenny Shiels replaced Alex Pursehouse with Zdenek Kroca, Paul Heffernan turned neatly inside the box to fire home after 34 minutes.
And Racchi scored a minute from time as the match looked destined for a draw.
St Mirren were unchanged after recent fine form and were on the front foot from kick-off at Rugby Park.
Goalkeeper Cammy Bell did well to dive low and turn away Steven Thompson's dipping drive from distance.
Only a last-ditch interception by Jeroen Tesselaar denied Heffernan a chance to open the scoring when the Kilmarnock striker controlled a Pursehouse through ball on his chest in front of goal.
However, the home side appeared disjointed, having been forced to do without the thrusting power of during training.
And McAusland sent a volley against the crossbar from a Graham Carey corner.
Killie failed to heed that warning and, a minute later, another Carey corner found Mair and goalkeeper Bell could only force the resulting header against the underside of the bar and into the net.
Shiels only waited until the half-hour mark to make a change, replacing midfielder Pursehouse, who had come into the side along with Matthew Kennedy, with centre-half Kroca.
It was a switch that required a change in formation that reaped immediate rewards.
First, Dean Shiels' low drive forced keeper Craig Samson to turn the ball past the post.
The Buddies failed to clear the resulting corner and Heffernan spun and struck a low shot into the bottom left corner from 10 yards.
It was now a much more even game and, after the break, St Mirren midfielder Aaron Mooy should have done better than fire over from 16 yards.
However, Kilmarnock were the slightly better side and Racchi bided his time on the edge of the box, switching cleverly from his right foot to his left before lofting the ball over Samson.
And St Mirren could not find an equaliser and allowed Killie to leapfrog them into seventh in the Scottish Premier League table.