Caley Thistle are just six points clear of the relegation play-off after a 1-0 defeat against Dunfermline.
James Craigen’s solitary goal proved decisive and with Dumbarton’s victory over Brechin City, the gap between Inverness in eighth and the Sons a place below has been reduced.
The visitors made three changes from the 2-0 defeat against Morton on February 24. Carl Tremarco and Jake Mulraney replaced Brad Mckay and Charlie Trafford and they were forced into a late third with Riccardo Calder limping out of the warm-up, with 16-year-old Cameron Harper handed his debut and Mckay drafted on to the bench.
Dunfermline made three changes, with Lewis Martin, Callum Morris and Kallum Higginbotham in for Jean-Yves M’Voto, Jason Talbot and Daniel Armstrong.
Harper went down five minutes into the game after Inverness conceded a free-kick, with Mckay coming on. The situation got worse for Robertson’s side as Craigen whipped the free-kick inside Mark Ridgers’ far post.
There was little for either team to shout of for the remainder of the half, with a couple of Inverness forays forward easily snuffed out by the Pars. Neither goalkeeper had a save to make and Caley Jags failed to register a shot on target, in what was a poor spectacle.
Craigen was in the hunt for a double early in the second half and forced Ridgers into a smart save at his near post, while at the other end Aaron Doran’s scuffed attempt was all Caley Thistle had to shout about.
Goalscorer Craigen had a couple of further attempts at goal but failed to trouble Ridgers, while Declan McManus had an effort cleared off the line and a further one that rebounded off the post.
Ridgers brilliantly denied a powerful strike from Kallum Higginbotham and Caley Jags assistant Brian Rice was sent to the stands late on in an underwhelming game for the visitors.