Ronnie O’Sullivan said he has had to change his thinking and “go back to basics” following a “hard year” after he thrashed Ali Carter 10-2 to reach the Tour Championship semi-finals.

The world number one, 48, got the better of Carter again after their ill-tempered Masters final in January, when O’Sullivan claimed his eighth title.

He will play Gary Wilson or Zhang Anda, who will resume tied 4-4 on Thursday.

Ding Junhui leads Mark Allen 5-3 overnight in Manchester.

The winner of that match will face Judd Trump or Mark Williams, whose quarter-final also takes place on Thursday.

Before their latest meeting, seven-time world champion O’Sullivan refused to speak about Carter, who he described as “not a nice person” and “a nightmare” to play against following their previous encounter.

But, after taking a commanding victory on Wednesday, O’Sullivan opened up about a difficult period which prompted him to speak to renowned psychiatrist Steve Peters.

“It’s been a hard year, drove myself pretty much insane really – it’s just got to me,” O’Sullivan, who withdrew from this year’s Welsh Open to protect his mental health, told ITV4.

“I had to go back to basics and get my head right. Deal with it because doing it the other way round isn’t working.

“Just getting my head around it is the only option I have left. I’ve driven myself mad for the last two years and not enjoyed any of it.”