Caley Thistle kept their outside chance of a promotion play-off place alive with a 1-0 away win against second-placed Livingston in the Championship.
Following a goalless first half, Inverness made the breakthrough just 28 seconds after the interval courtesy of Liam Polworth’s excellent strike.
John Robertson’s men held on to keep their promotion hopes mathematically alive going into the last day, with Inverness needing to win at Morton and hope Dunfermline lose against Dumbarton in order to finish fourth.
Caley Jags made one change from the side that was agonisingly held to a late 2-2 draw by Dunfermline on Saturday, with Connor Bell drafted in to replace Nathan Austin.
Inverness started brightly but Mark Ridgers had to be alert to keep the home side out, making fine diving saves to deny Adam Frizzell and Ryan Hardie.
The Highlanders struggled to create chances of their own in the first half, with Polworth seeing a long-range effort deflected narrowly over midway through the opening 45 minutes.
Polworth was to have far more joy with his next attempt instantly after the restart, with the midfielder being teed up by George Oakley before letting fly with a low 25-yard drive that sailed past Gary Maley.
Inverness had opportunities to kill off their opponents, with Joe Chalmers shooting straight at Maley following good work from Polworth, who subsequently squeezed over from an acute angle following Bell’s near post flick, however Inverness held firm with some excellent defending required to claim the points.