Ronnie O'Sullivan turned his 5-3 overnight lead over Stephen Maguire, the 2004 UK champion, into a 9-3 victory in York yesterday.

O'Sullivan made four superlative frame-winning breaks, 82, 66, 100 and 110, the last including - uniquely it is understood - pinks with all 15 reds, as the black was left out of commission in the middle of the baulk cushion.

O'Sullivan did note that the pockets appeared excessively receptive and the degree of bounce from the cushions seemed so unpredictable that "I tried to play without using them".

But such was the quality of his performance that it was still difficult to understand why he has not won a ranking title since the Irish Masters of March 2005.

John Higgins, who made centuries in three consecutive frames in his opening session against Stephen Lee, compiled another, 102, in completing his 9-2 win as he too qualified for the quarter-finals.

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