John Higgins punished an unforgivable series of mistakes by Ronnie O’Sullivan tonight as he came out on top in their Betfred.com World Championship quarter-final.

Mark Selby let Ronnie O’Sullivan off the hook as an intriguing first session between two of snooker’s most potent potters was littered with mistakes and finished all square.

Ronnie O’Sullivan resisted a doughty challenge from Mark Williams to edge through 13-11 in their 888.com World Championship quarter-final at Sheffield’s Crucible Theatre tonight.