The Belgian – who admitted after his 13-10 quarter-final win that he got “drunk as hell” following his victory over Mark Williams in the previous round – had not won a single match at the Crucible in his previous five visits to Sheffield.

Trailing 10-6 overnight, the match seemed set-up for O’Sullivan to cruise into the semi-finals in pursuit of a record eighth world title. But, helped with some uncharacteristic errors from O’Sullivan who failed to make a single break over 30, 28-year-old Brecel took just 75 minutes to reel off seven successive frames to clinch victory.

“To win seven frames in a row against Ronnie is probably the best session I have played,” said Brecel. “I was so composed for the whole match, I felt very calm, even at the end.

SHEFFIELD, ENGLAND - APRIL 26: Ronnie O'Sullivan of England reacts during their Quarter Final match against Luca Brecel of Belgium on Day Twelve of the Cazoo World Snooker Championship 2023 at Crucible Theatre on April 26, 2023 in Sheffield, England. (Photo by George Wood/Getty Images)

“I struggled at the Crucible many times but it has all changed suddenly and I don’t know why. I feel so good here now and I have not struggled to get over the line in my three matches. If I wasn’t happy off the table then I wouldn’t be able to play like this.”

Brecel also revealed his unorthodox partying preparation to beating the seven-time world champion.

Brecel told the BBC: “Before the tournament I was out partying and staying up late until 6 or 7am, playing FIFA with my friends, having drinks and not practising.

“Even after I beat Mark Williams I got home at 7am by car, and that same day we went out again until five or six in the morning.

Ronnie O'Sullivan reacts during his match against Luca Brecel (not pictured) on day twelve of the Cazoo World Snooker Championship at the Crucible Theatre, Sheffield. Picture date: Wednesday April 26, 2023. PA Photo. See PA Story SNOOKER World. Photo credit should read: Zac Goodwin/PA Wire.

RESTRICTIONS: Use subject to restrictions. Editorial use only, no commercial use without prior consent from rights holder. — Ronnie O'Sullivan reacts during his match against Luca Brecel (not pictured) on day twelve of the Cazoo World Snooker Championship at the Crucible Theatre, Sheffield. Picture date: Wednesday April 26, 2023. PA Photo. See PA Story SNOOKER World. Photo credit should read: Zac Goodwin/PA Wire. RESTRICTIONS: Use subject to restrictions. Editorial use only, no commercial use without prior consent from rights holder.

“I was drunk as hell. The next day I had to drive back up again, so it’s a totally different preparation.”

Brecel, winner of two major rankings tournaments – the 2021 Scottish Open and 2022 Championship League – immediately imposed himself on O’Sullivan after both players had opportunities to win a scrappy initial frame.

O’Sullivan then inexplicably missed a black off its spot and Brecel split the pack of reds to take advantage with a 112 clearance.

The next frame followed the same pattern as O’Sullivan, stretching over a long red, let in Brecel again.

Brecel capitalised with a 64 break and, although he missed a red that would have left O’Sullivan requiring a snooker, he eventually reduced arrears to 10-9.

The scores were level when O’Sullivan lost position again and Brecel got among the balls for a 72 break. O’Sullivan was in desperate need of the interval, but contributions of 61, 78 and 63 ended the contest in quick fashion and put the 47-year-old out of his misery.

O’Sullivan said: “Luca was phenomenal, brilliant, amazing. What a player, what a talent. I’ve never seen a talent like that before. No one plays like that, it’s impossible. That was confident, solid, assured. I don’t think he realises how talented he is, it’s very hard for you to see your own gift, other people see it. But he is one gifted snooker player.”

Mark Allen reached the semi-finals with a hard-fought 13-10 win over qualifier Jak Jones.

World Snooker Championship: Brecel inflicts Crucible hangover on rival O’Sullivan