Second-half goals by Liam Kelly and Craig Bryson at St Mirren Park gave Kilmarnock their seventh win in 10 Scottish Premier League games.
Cammy Bell saved a great hook shot from Saints' Darren McGregor in an entertaining first half but after the break Killie stepped up a gear.
In 64 minutes a quick free-kick by Alexei Eremenko to Jamie Hamill gave Kelly an easy goal from three yards.
Then Bryson, the visitors' captain, sealed the win with a 25-yard shot.
St Mirren were five points ahead of basement side Hamilton at kick-off, though the Lanarkshire men had two games in hand.
Danny Lennon paired former Killie striker Craig Dargo and Michael Higdon in attack and the latter had two attempts in quick succession early in the match.
Dargo played the ball wide to David van Zanten and the Irishman's cross landed on the head of Higdon, who directed it harmlessly over the bar.
Then, as if to silence the mocking cheers of the 2,500 travelling fans, the Englishman thumped an effort from 40 yards. With Bell six yards off his line, the shot flew just a foot over.
In the pre-match managerial spiels Lennon demanded greater concentration and Mixu Paatelainen warned his Kilmarnock players against complacency.
While the Saints had lost a number of games by the odd goal, Kilmarnock had enjoyed an excellent run of form that had produced six wins and two draws in their last nine SPL matches.
But there were no signs of the Rugby Park side assuming a win would fall into their lap. Instead they carved out a series of chances.
Eremenko had a long-range free-kick saved by Gallacher, then in 28 minutes, when Mehdi Taouil was hauled to the turf on the edge of the box by Marc McAusland, the Saints keeper threw himself to his right to save from the classy midfielder.
Kelly celebrates the opening goal for Kilmarnock
St Mirren's best chance of the opening 45 came from an unlikely source, but Bell made a great save from defender McGregor's volleyed hook shot.
Three minutes before the break Conor Sammon wasted a glorious chance to put Killie ahead when, six yards out, he flapped at a cross from Ben Gordon and as he moved in to makes amends for his mis-kicked shot Gallacher somehow scrambled the ball to safety.
This fixture may not have quickened pulses in previous seasons but Killie's winning habit and the Buddies attacking set-up produced plenty of goalmouth action in the second half and a few spurned chances at each end.
The chance presented on a plate to Taouil by Sammon was as inviting as a favourite meal, yet the diminutive Moroccan completely missed the big forward's cut-back and the opportunity was gone.
Higdon maintained the stalemate when he side-footed an effort over the bar from seven yards when a lighter touch would have surely tested Bell.
Lennon swapped Dargo and McAusland for Wardlaw and Kenneth McLean but they had no time to make any impact before Killie scored their first goal, one that will have left Lennon quivering with rage.
In 64 minutes the Saints defence switched off at a free-kick; Eremenko did not. Instead, he fed the ball to Jamie Hamill and his pass across the goal was knocked into the net from close range by Kelly for his fourth goal in as many games.
An untidy spell followed before Killie's captain Bryson settled the match with a deflected shot from 25 yards that flew over Gallacher into the roof of the net, the culmination of a direct attack from keeper Bell via midfielder Taouil.
The Ayrshiremen were bottom of the league earlier in the season. Now they boast a record of only one defeat, by Rangers, in their last 10 league contests.
For the Paisley hosts, they remain mired in the relegation zone but their endeavour will have heartened Lennon and fans alike.
90:00+3:12 The referee blows for offside against Jamie Hamill. Paul Gallacher restarts play with the free kick.
90:00+3:01 Liam Kelly produces a cross.
90:00+2:25 Corner taken by Alexei Eremenko.
90:00+2:05 Foul by Lee Mair on Marinho Rui Miguel, free kick awarded. Direct free kick taken by Alexei Eremenko.
90:00+0:28 James Fowler gives away a free kick for an unfair challenge on Jure Travner. Direct free kick taken by Paul Gallacher.
89:43 Substitution Marinho Rui Miguel replaces Conor Sammon.
89:43 Substitution David Silva replaces Ben Gordon.
89:43 Substitution Garry Hay replaces Mehdi Taouil.
87:31 Effort from the edge of the area by Mehdi Taouil goes wide of the left-hand upright.
87:01 Kenneth McLean crosses the ball, James Fowler makes a clearance.
86:34 The ball is crossed by Craig Bryson, comfortable save by Paul Gallacher.
85:43 Booking Jamie Hamill is booked.
84:56 The ball is crossed by Kenneth McLean.
82:40 Effort on goal by Liam Kelly from just inside the penalty area goes over the target.
82:10 Effort on goal by Sean Lynch from a long way out goes over the bar.
81:02 Unfair challenge on Mohamadou Sissoko by Gareth Wardlaw results in a free kick. Jamie Hamill takes the direct free kick.
80:11 The ball is swung over by Kenneth McLean.
78:19 Mehdi Taouil provided the assist for the goal.
78:19 GOAL - Craig Bryson:St Mirren 0 - 2 Kilmarnock Craig Bryson fires in a goal from long range to the bottom right corner of the goal. St Mirren 0-2 Kilmarnock.
78:02 David van Zanten sends in a cross, Cameron Bell makes a comfortable save.
77:10 The referee blows for offside against Jamie Hamill. Paul Gallacher restarts play with the free kick.
73:38 Alexei Eremenko takes a outswinging corner.
73:32 Conor Sammon produces a cross, blocked by Darren McGregor.
72:10 Darren McGregor gives away a free kick for an unfair challenge on Conor Sammon. Jamie Hamill restarts play with the free kick.
72:01 The ball is crossed by Jure Travner, Liam Kelly manages to make a clearance.
71:40 The ball is crossed by Craig Bryson, clearance by Kenneth McLean.
70:55 Craig Bryson produces a right-footed shot from outside the penalty box and misses wide left of the target.
70:36 Corner taken short by Mehdi Taouil.
70:28 The ball is swung over by Ben Gordon.
69:45 Patrick Cregg has an effort at goal from outside the area missing to the wide right of the goal.
69:38 Kenneth McLean crosses the ball.
69:04 Paul McGowan concedes a free kick for a foul on Craig Bryson. Alexei Eremenko takes the free kick.
68:07 Inswinging corner taken by Jure Travner from the right by-line played to the near post, Close range headed effort by Michael Higdon misses to the right of the target.
67:47 Corner taken by Paul McGowan.
67:40 The ball is delivered by David van Zanten, Ben Gordon gets a block in.
66:15 Outswinging corner taken from the right by-line by Patrick Cregg.
66:08 The ball is crossed by Patrick Cregg, blocked by Liam Kelly.
66:00 The ball is swung over by David van Zanten, Frazer Wright manages to make a clearance.
63:42 The assist for the goal came from Jamie Hamill.
63:42 GOAL - Liam Kelly:St Mirren 0 - 1 Kilmarnock Liam Kelly gets on the score sheet with a goal from close in to the bottom left corner of the goal. St Mirren 0-1 Kilmarnock.
63:12 Mehdi Taouil fouled by Jure Travner, the ref awards a free kick. Direct free kick taken by Alexei Eremenko.
62:07 Jure Travner crosses the ball.
60:30 David van Zanten gives away a free kick for an unfair challenge on Craig Bryson. Free kick crossed by Alexei Eremenko, Lee Mair manages to make a clearance.
59:09 Substitution Gareth Wardlaw comes on in place of Craig Dargo.
59:09 Substitution Kenneth McLean replaces Marc McAusland.
58:31 Alexei Eremenko has an effort at goal. Save by Paul Gallacher.
58:03 Paul McGowan has an effort at goal from just inside the box that misses to the left of the goal.
57:15 Short corner taken by Alexei Eremenko.
57:03 Shot by Liam Kelly from 12 yards. Paul McGowan gets a block in.
55:02 The official flags Conor Sammon offside. Free kick taken by Paul Gallacher.
54:20 Volleyed right-footed shot by Paul McGowan. Blocked by Craig Dargo.
53:39 Sean Lynch fouled by Liam Kelly, the ref awards a free kick. Direct free kick taken by Patrick Cregg.
52:31 The referee blows for offside. Cameron Bell takes the indirect free kick.
52:15 The ball is sent over by Marc McAusland, clearance made by Frazer Wright.
51:56 Jure Travner crosses the ball, Mohamadou Sissoko makes a clearance.
51:03 The ball is sent over by Paul McGowan, Shot from deep inside the area by Michael Higdon clears the bar.
50:57 The ball is swung over by Jure Travner, clearance by Mohamadou Sissoko.
49:07 Jamie Hamill concedes a free kick for a foul on Paul McGowan. The free kick is swung in right-footed by Patrick Cregg, clearance by Conor Sammon.
48:50 The ball is delivered by Sean Lynch, clearance made by Jamie Hamill.
48:44 Jure Travner crosses the ball, Jamie Hamill manages to make a clearance.
48:34 The ball is sent over by Michael Higdon, Mohamadou Sissoko manages to make a clearance.
48:25 A cross is delivered by David van Zanten.
47:50 Centre by Liam Kelly, Marc McAusland makes a clearance.
47:26 Centre by Conor Sammon.
45:23 Free kick awarded for a foul by Sean Lynch on Liam Kelly. Direct free kick taken by Alexei Eremenko.
45:01 The second half kicks off.
Half Time
45:00+0:16 The whistle is blown to end the first half.
45:00+0:06 Centre by Jure Travner, clearance made by Frazer Wright.
43:28 The assistant referee signals for offside against Jamie Hamill. Paul Gallacher takes the indirect free kick.
42:41 The ball is delivered by Ben Gordon, Shot from 6 yards from Conor Sammon. Save made by Paul Gallacher.
42:02 The ball is delivered by Marc McAusland, Craig Dargo produces a right-footed shot from inside the area that goes over the bar.
39:39 The ball is delivered by Marc McAusland, blocked by Ben Gordon.
38:35 Effort from long distance by Mehdi Taouil goes wide right of the target.
36:31 Conor Sammon is flagged offside by the assistant referee. Indirect free kick taken by Paul Gallacher.
36:02 The ball is crossed by Michael Higdon, Cameron Bell makes a comfortable save.
35:03 Corner taken by Paul McGowan played to the near post, Craig Bryson manages to make a clearance.
34:42 Darren McGregor has an effort at goal from 18 yards. Fantastic save by Cameron Bell.
34:03 Inswinging corner taken right-footed by Paul McGowan played to the near post, Craig Bryson manages to make a clearance.
31:47 Mehdi Taouil concedes a free kick for a foul on Patrick Cregg. The free kick is delivered right-footed by Patrick Cregg from right wing, Mohamadou Sissoko manages to make a clearance.
31:24 Jure Travner delivers the ball, Cameron Bell makes a comfortable save.
29:18 Alexei Eremenko takes the outswinging corner, Conor Sammon challenges Sean Lynch unfairly and gives away a free kick. Direct free kick taken by Paul Gallacher.
28:59 Shot by Craig Bryson. Save made by Paul Gallacher.
28:03 Free kick awarded for an unfair challenge on Mehdi Taouil by Marc McAusland. Shot on goal comes in from Alexei Eremenko from the free kick, Paul Gallacher makes a fantastic save.
28:03 Booking The referee books Marc McAusland for unsporting behaviour.
26:02 Free kick awarded for an unfair challenge on Paul McGowan by Jamie Hamill. Direct free kick taken by Patrick Cregg.
24:46 Jure Travner produces a cross.
23:22 Jamie Hamill gives away a free kick for an unfair challenge on Jure Travner. Direct free kick taken by Paul Gallacher.
22:00 Free kick awarded for an unfair challenge on Conor Sammon by Lee Mair. Alexei Eremenko fires a strike on goal direct from the free kick, save by Paul Gallacher.
21:49 The ball is crossed by Jamie Hamill, Marc McAusland makes a clearance.
Correction - 15:42 Effort from long distance by Michael Higdon goes wide right of the goal.
15:42 Mehdi Taouil produces a right-footed shot from long range which goes wide right of the goal.
15:26 Centre by Alexei Eremenko, Darren McGregor manages to make a clearance.
14:45 Alexei Eremenko takes a outswinging corner to the near post, Darren McGregor manages to make a clearance.
14:28 David van Zanten is ruled offside. Free kick taken by Cameron Bell.
10:52 Outswinging corner taken from the right by-line by Paul McGowan.
10:28 Inswinging corner taken by Paul McGowan, clearance by Conor Sammon.
9:49 Craig Bryson fouled by Patrick Cregg, the ref awards a free kick. Frazer Wright takes the free kick.
9:49 Booking Booking for Patrick Cregg.
9:09 Free kick awarded for an unfair challenge on Sean Lynch by Mehdi Taouil. Direct free kick taken by Patrick Cregg.
7:40 Ben Gordon challenges David van Zanten unfairly and gives away a free kick. Patrick Cregg crosses the ball in from the free kick.
7:05 Ben Gordon sends in a cross.
6:00 Effort on goal by Michael Higdon from long distance goes harmlessly over the target.
5:25 Marc McAusland crosses the ball, Header from deep inside the penalty area by Michael Higdon goes harmlessly over the crossbar.
4:30 Corner from the right by-line taken by Alexei Eremenko, Marc McAusland fouled by Frazer Wright, the ref awards a free kick. Paul Gallacher takes the direct free kick.
4:16 Jamie Hamill takes a shot. Blocked by Sean Lynch.
3:13 Patrick Cregg gives away a free kick for an unfair challenge on Mehdi Taouil. Alexei Eremenko shoots direct from the free kick.
2:07 Patrick Cregg challenges Alexei Eremenko unfairly and gives away a free kick. Alexei Eremenko takes the free kick.
1:57 The ball is sent over by Marc McAusland.
0:31 A cross is delivered by Mehdi Taouil.
0:00 The referee starts the match.
Live text and data provided by The Press Association.
E-mail this to a friend 
Printable version 
Bookmark with:
What are these?