In snooker we reserve our affection for the slightly nuts. Ever since colour arrived and made snooker a classic television sport, we have revelled in a dynasty of mad geniuses: a series of unreliable men of unpredictable talent, all capable of scandal and excess, but on their day elevating a curious indoor pastime into something not far short of kinetic art.

In the beginning was the hurricane: Alex Higgins, who won two world titles at the Crucible. His talent for snooker makes you think he should have won far more, but his lack of talent for practically everything else makes you realise that two championships was not far short of miracle. A gift for playing snooker shots is not the same thing as a talent for winning snooker tournaments. 

Jimmy White, second of the dynasty, showed us that. He was the most brilliant player of his generation when it came to playing shots. He gave us best shots, best breaks, best frames. But he never won the World Championship: runnerup six times. He could do everything but win. And then came Ronnie O’Sullivan: perhaps in terms of pure ball-striking talent better than either of the others two – and what’s more, capable of playing left-handed almost as well as right. And in craziness he could give anyone a match, especially in his younger days. 

Snooker is about control. You control the ball you aim for, seeking to put it in the pocket, but crucially, you must also control the white ball, the cue ball, the ball you strike. So far, so basic: but when Higgins, White and O’Sullivan played their best, they seemed to create a gorgeous dance involving every ball on the table, so that the colours created dazzling patterns.

And it’s those storms of beauty that keep people coming back to snooker: especially when the World Championship takes over our screens. But this is not beauty you can rely on. O’Sullivan can sometimes sustain it for three or even four frames at time: as glorious to watch as it must be devastating to experience. We look out for O’Sullivan’s matches in hope of catching such a storm… and cheer for him even when he’s less fluent, out of gratitude for what we remember.

He can’t do it every time. That truth used to destroy him. In snooker perfection can seem almost attainable, and O’Sullivan has often come within reach… but then his level would inevitably drop and he would slip into black moods of despair and self-loathing.

How many times has O’Sullivan threatened to quit? He “retired” for the first time aged 18 and has been retiring and unretiring ever since. But he has come to terms with his turbulent nature and his fallibility, and has now won the World Championship five times.  

He has learned to live with his genius; he’s worked with the sports psychologist Steve Peters and accepted the elusive nature of perfection, and the fact that his brilliance comes and goes like Karma Chameleon. He has taken control of things that had seemed uncontrollable, mostly by means of running, which gives him an escape from the stresses of his sporting life.

O’Sullivan has done the best of this dynasty of mad geniuses. Is that because of some kind of essential stability? Or because we’re all more tolerant of mental fragility than we used to be? All of us – Ronnie included – understand that O’Sullivan’s fragility is an essential part of his genius… so we salute his achievements as the World Championship comes round again, and we begin to wonder if, at the age of 41, he’s got another world title within him.

Snooker: World Championship is on from Saturday at 10am on BBC2, Eurosport 1 and 2, and 1:15pm on BBC1