Caley Thistle’s hopes of Premiership survival suffered a massive blow as they were defeated 3-0 by St Johnstone at Caledonian Stadium.
Inverness had much of the possession but were unable to convert any of their chances, with goals from Steven MacLean, Liam Craig and Graham Cummins securing victory for the Perth side.
The result means Inverness are now further adrift at the foot of the table, with four points separating them from Hamilton Accies and Motherwell.
Inverness made three changes from the side defeated 1-0 by Aberdeen in midweek, with Liam Polworth and Henri Anier dropping to the bench and David Raven sidelined with a groin injury, meaning Jamie McCart, Larnell Cole and Alex Fisher were drafted in.
Inverness started well and could have taken the lead on eight minutes, when Greg Tansey’s corner found the head of Fisher, but his effort was inadvertently deflected over by team-mate Carl Tremarco.
Saints had a fine chance of their own on 12 minutes, when Brian Easton’s delivery picked out the head of Graham Cummins, who guided his effort inches past the post.
Inverness began to take command though, with Fisher heading another effort wide from Kevin McNaughton’s cross, before Tremarco stabbed wide following another corner.
Saints goalkeeper Alan Mannus was called into action for the first time on 32 minutes when Ross Draper flicked the ball through for Billy Mckay, however the attacker was thwarted by a quick block from his fellow Northern Irishman.
Caley Jags were firmly in control and Cole came close on 39 minutes, when he drilled low effort wide from the edge of the area.
Saints stunned the hosts by taking the lead against the run of play on 40 minutes, as Michael Coulson’s cross was parried out by Owain Fon Williams before falling into the path of MacLean, with the attacker bundling home from close-range despite Gary Warren’s best efforts to clear off the line.
Inverness should have levelled within 60 seconds, with Cole going through on goal before seeing his shot saved by Mannus, however Saints spurned an excellent chance to score a second on the stroke of half-time, as Liam Craig’s corner was somehow bundled over by Graham Cummins at the far post.
The goal allowed Saints to tighten the game up in the second-half, with Inverness unable to create as many opportunities, with Tansey seeing his effort palmed away by Mannus, before Cole was also denied by the goalkeeper and King trundled the rebound wide.
Caley Jags’ chances were all but ended on 81 minutes when Larnell Cole was shown two yellow cards in immediate succession for dissent following a tackle on the Englishman.
Saints were awarded a penalty on 88 minutes, when Tremarco tripped Cummins inside the box and Craig sent Fon Williams the wrong way from the spot.
Cummins added a third from close-range moments later, while Craig remarkably nearly added a fourth when he saw his long-range effort crash off the crossbar on a miserable day for Inverness.