Ronnie O'Sullivan's campaign for a third world championship title ended last night when the bookmakers' favourite finally succumbed¹ 13-9 to John Higgins after fighting intensely to stage a comeback from six frames behind.

The bulk of the damage was inflicted² in the morning session as O'Sullivan, every department of his game malfunctioning³, descended⁴ from 4-4 to an 11-5 deficit⁵. Higgins, the 1998 champion, crucially stole two frames, the 14th and 16th, on the black from well adrift but to his credit O'Sullivan, a player who has often accepted his perceived fate too early, rallied determinedly⁷ last night.

Earlier, Shaun Murphy had produced the greatest quarter-final fightback in the 30 years that this theatre has staged the world championship by recovering from five down with six to play to beat Matthew Stevens 13-12. "I'd seen what had happened to Matthew and of course it was on my mind," said Higgins, who did not pot a ball as O'Sullivan swiftly rallied from 12-7 to only 12-9 in arrears⁸. It was therefore with immense relief that Higgins controlled the 22nd frame to set up an all-Scottish semi-final against Stephen Maguire, who accounted for Anthony Hamilton 13-7.

"It's disappointing not to still be a part of the championship but at least I've found a bit of alignment⁹ towards the end," said O'Sullivan, who has not won a world- ranking event since the Irish Masters of March 2005. "Overall my technique let me down and I never felt as though I could completely keep John out."

Murphy, the 2005 champion, overcame Stevens after a final session of 3hr 40min during which the tension undermined fluency¹⁰ but engrossingly¹¹ enhanced drama. "I had the game won at 11-5," said Stevens. "I missed a few chances. I should have won 13-7 when I was clearing up the colours but I just couldn't get over the line. I felt all right but the tension built up."

Murphy had resumed yesterday "never seriously believing I could win" but, as he noted¹² Stevens slowly succumbing¹³ to "clinchers disease", he remembered Ken¹⁵ Doherty's extraordinary 17-16 semi-final victory over Paul Hunter in 2003 from 15-9 down and a few occasions when Stevens himself had failed to clinch¹⁴ a winning position.

The only cloud on Murphy's horizon is his rift⁶ with his father, Tony, previously¹⁶ the driving force in his career, with whom he has not spoken for 18 months. "He said a lot of stuff which just wasn't acceptable. He owes me an apology and unless he rings me to say sorry I don't know when we'll speak," said the 24-year-old. "I just had to stick up for myself."

As for Stevens, the promise of redemption after a disappointing season has ended in relegation¹⁷ from the elite¹⁸ top 16. He has reached two finals here, losing 18-16 in 2000 to his fellow Welshman Mark Williams from 13-7 ahead and two years ago to Murphy, 18-16, having led 10-6 after the first day's play.

Maguire made breaks of 96, 137 and 108 in the four frames he needed yesterday to give him a maiden¹⁹ semi-final appearance here. Hamilton did not pot a ball.

Murphy's semi-final opponent will be Mark Selby, who beat Allister Carter 13-12 after 9hr 10min play in a midnight finish. A crumb²⁰ of consolation²¹ was that Carter's 144 break became the front runner for the 10,000 pounds highest break prize.