JOHN ROBERTSON let rip at experienced campaigners in his squad who have piled early season pressure on Inverness Caley Thistle through basic mistakes.

In a scathing assessment of Saturday’s 3-1 home defeat to Livingston, the Highlanders’ manager said he understood why supporters had booed his team from the field.

Robertson, while acknowledging a positive performance for the first hour, berated his players for squandering goalscoring opportunities and making simple defensive mistakes.

He was also highly-critical of the lack of impact made by substitutes who had previously demanded to know why they were not being selected.

After just one win from six opening Championship matches, last season’s relegated Premiership club sit nine points behind the leaders and two points off bottom place.

Robertson said: “We’re asking players to do basic things and these basic things are costing us.

“Players get free from set pieces – basic. Players not going with runners – basic. Players not pulling the trigger to shoot – basic.

“There’s a mental block we’re going to have to get over, and quickly.

“That’s two weeks in a row where, had we taken our chances at the right time, we could have been sitting on the coat-tails of the leaders.

“We’re not. We find ourselves in the bottom three, looking over our shoulders at what’s below us.

“The last half hour against Livingston was a performance that puts everyone here under pressure. It puts players under pressure, coaching staff under pressure – but we have to deal with it.”

Robertson, addressing the jeers from the stands, said: “Listen, the fans are quite right. We’ve got to give them something to cheer about.

“We did that in the first half, even after we went behind. I thought the fans were behind us and knew we were unlucky not to be in front.

“When Livingston went 2-1 ahead, you could understand them starting to grumble because they’ve seen us spurn many opportunities.

“There was a wee spell at 2-1 where we’ve created some wonderful chances but not pulled the trigger.

“Liam Polworth has a glorious chance where, in training, he’d have curled it into the corner. Instead, he tried to pick somebody out in the middle.

“That’s when the frustration starts. We’re trying to score the perfect goal rather than just smash it into the back of the net.

“You could hear the frustration growing and when their guy hits the third goal you can understand why the fans aren’t happy.

“I’m not happy. The coaching staff are not happy, so why shouldn’t the fans be unhappy? We have no issues in that regard.

“This is where players have to be strong and stand up to it.

“That was the disappointing aspect. At 3-1 behind, we started to chase the game without discipline, running into positions which were not natural.”

Turning his wrath on the substitutes, Robertson exempted Carl Tremarco, back after April’s cruciate injury, from criticism.

But he said: “You’re asking substitutes to go on and make an impact – and we got nothing.

“Carl Tremarco got forward down the lines, but the other two went on and barely registered a touch, barely did anything.

“And these are the guys who are knocking on your door asking why they’re not in the team. When they are given their opportunity, they show you nothing.

“We’ve been loyal and have worked hard to get the right people for the right positions. We seemed to be making progress.

“But once we lost the second goal, we fell apart – and that’s the worrying thing. Experienced players are making basic errors.”