St Johnstone 3 Inverness CT 0
St Johnstone deepened Inverness' relegation woes with a 3-0 win in the Highlands.
Steven MacLean's deflected shot and a late penalty from Liam Craig ensured the Saints closed the gap on Rangers in third to just three points, with Graham Cummins stoppage-time strike putting icing on the cake.
With Hamilton drawing with Ross County, the gap to safety is now four points for Richie Foran's side, who face a do-or-die trip to Motherwell next week.
A sending off for Larnell Cole for two rapid bookings summed up their afternoon, with the team effectively downing tools after going down to 10 men.
Caley Thistle made three changes from the side that lost to Aberdeen, with Alex Fisher, Jamie McCart and Larnell Cole in for Henri Anier, David Raven and Liam Polworth. St Johnstone made the one change from midweek, swapping Michael Coulson for David Wotherspoon.
Fisher was making his first start since September, having returned from three months in the cold in the loss at Pittodrie. He came close to making an immediate impact, leaping to meet a Greg Tansey corner that was deflected over by his own team-mate Carl Tremarco.
Both teams traded further headed chances, with Graham Cummins drifting one past Owain Fon Williams's far post and Fisher flinging himself at a Kevin McNaughton cross that went just wide.
Inverness were having by far the better chances and Tremarco failed to make the most of a good opportunity to get his eighth of the season, watching a Gary Warren header drop at his feet from a corner but scuffing the volley wide.
Cole had a couple of chances, dragging one wide and hitting another straight at Alan Mannus, but such has been the theme of Caley Thistle's season, it seemed obvious goal was going to come at the other end.
Michael Coulson's cross was palmed out by Fon Williams to MacLean on the six-yard line and despite Warren and McCart's efforts on the line, succeeded in finding the back of the net.
The start of the second half was a tepid affair, with Caley Thistle again seeing plenty of the ball without doing anything meaningful with it.
It took until the 67th minute for the hosts to threaten through Tansey but Mannus got down to parry. Joe Shaughnessy was on hand to clear before Billy Mckay could pounce.
Mannus was equal to a Cole effort from distance and Billy King skewed the rebound wide, as the Caley Jags desperately sought an equaliser.
Cole earned his marching orders for two quick-fire yellow cards, apparently for dissent, as Inverness's cause worsened.
Chris Millar wasted a glorious opportunity to double the lead but Craig made sure of the points, tucking away from the spot when Tremarco felled Cummins.
Craig smacked another effort off the bar and Cummins dragged a shot wide as the Saints threatened to humiliate Inverness, who fell to pieces in a worrying finale.