In a match that has lived up to expectations, Ronnie O’Sullivan and Mark Williams continued a battle royal at the Crucible last night. O’Sullivan leads 9-7, but his participation in the quarter-finals of the 888.com World Championship is in the balance.

O’Sullivan, the champion in 2001 and 2004, inflicted an early blow by stealing the tenth frame on the black with a 48 clearance to lead 6-4 and smoothly compiled a 102 break in the twelfth to move 7-5 ahead. Williams, who must reach the semi-finals to remain in the top 16 of the world rankings for a thirteenth consecutive season, looked as if he would be swamped as O’Sullivan increased the gap to 9-5.

A missed black from its spot cost Williams in the thirteenth and O’Sullivan’s run of 78, direct from his opponent’s clumsy in-off, was the decisive visit of the fourteenth.

The momentum shifted, however, in the next frame. O’Sullivan risked a plant that went badly astray, splitting the reds. Williams capitalised with 81 and then, in the last frame of the session, with 73 to stay in touch.

Neil Robertson trails Stephen Maguire 11-5, but at least has the satisfaction of avoiding one of the heaviest losses in 31 years of snooker at the Crucible. When Maguire led 9-0, the possibility of an unprecedented whitewash could not be discounted. However, showing stubborn professional pride, Robertson restored respectability.

Stephen Hendry will never be a grinder but the Scottish king of the Crucible has become canny. Heeding the advice of a former corner man for Peter Ebdon, Hendry is resisting the attacking temptations that have undermined his efforts in recent years.

At 39, Hendry is no young buck who can rely on potting skills alone, yet a macho pride has prevented him from abandoning a game plan based almost exclusively on aggression. That is, until he absorbed the guidance of Chris Henry. In 2002, Henry provided invaluable backstage support as Ebdon beat Hendry 18-17 in the world final. He is a coaching disciple of Frank Callan, who resurrected many a career, and is a deeply analytical thinker about the game.

From the moment he joined forces with Hendry last year, Henry realised that to win an eighth World Championship his client had to strike a strategic balance between circumspection and fluency. This Hendry did unswervingly during the 13-7 win over Ding Junhui that carried him to a record seventeenth Crucible quarter-final - two more than Jimmy White.

“Chris told me that the amount of matches I’ve cost myself with bad shot selections in the past few years has been incredible. One of my biggest faults has been pushing the boat out when I should be more careful,” Hendry, who now plays Ryan Day, said. “This place feels like my living room, with pipe and slippers and my feet under the table.”

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