Livi’s top six hopes suffered a dent as Callum Hendry’s late strike gave St Johnstone all three points in a turgid encounter at McDiarmid Park.
In an otherwise entirely forgettable afternoon, the striker volleyed home a Drey Wright cross from close range six minuets from time for the only goal of the game.
The defeat means the Lions are now just three points above seventh-placed Saints in the battle for a top six place – with three games remaining before the split.
Livingston boss Gary Holt made three changes to the line-up from their midweek draw at home to Celtic.
Captain Marvin Bartley returned having featured as a substitute in that game while Nicky Devlin made his first appearance since sustaining a knee injury in October. Jack McMillan also earned a recall. Out went Scott Robinson, Steve Lawson and Aaron Taylor-Sinclair.
The hosts looked the better side in the early goings on but it was Livi who squandered the first chances of the contest when Efe Ambrose tamely hit a free-kick from 20 yards out against the wall and then a few minutes later saw his header at the back post comfortably saved by Zander Clark.
The Saints went close to taking the lead on 17 minutes with their first effort on goal. Stevie May’s glancing header from a Jason Kerr cross was parried by Robby McCrorie.
The poor pitch and blustery conditions meant there was always the chance of mistakes being the difference – and so it almost proved midway through the first half as Steven Lawless pounced on a poor defensive header but his powerful first-time half-volley from 25 yards was brilliantly tipped over by Clark.
Lawless went close once more on 33 minutes when Bartley’s through ball found the winger with his angled drive looking set to nestle inside Clark’s left-hand post – only to agonisingly trundle wide.
Half-time: St Johnstone 0-0 Livingston
While the first half was poor, the second half was even worse with the first moment of interest not arriving until 35 minutes in when Clark almost spilled a Scott Pittman long range effort into the path of the onrushing Lyndon Dykes.
With the game seemingly destined to end in a dull draw, the Saints got themselves in front six minutes from time as Hendry was left unmarked to emphatically slam home a pinpoint Drey Wright cross.
Full-time: St Johnstone 1-0 Livingston
St Johnstone: Clark, Kerr, Gordon, McCart, Wright, Tanser, Butcher, McCann, Holt (Wotherspoon 80), Hendry (Kane 88), May (O’Halloran 71)
Subs not used: Parish, Booth, Jones, Ralston,
Goals: Hendry (84)
Livingston: McCrorie, McMillan (Taylor-Sinclair 78), Brown, Ambrose, Guthrie, Devlin, Bartley, Sibbald (Robinson 72), Pittman, Lawless (Jacobs 74), Dykes
Subs not used: Schofield, Lawson, Crawford, Souda
Referee: Kevin Clancy
Match Report: Andy Crawford