Masters: Ronnie O'Sullivan beats Marco Fu 6-0 at Alexandra Palace

Ronnie O'Sullivan said he was suffering dizzy spells despite thrashing Marco Fu 6-0 with a sublime performance to ease into the quarter-finals of the Masters.

The 42-year-old, looking to extend his record number of Masters titles to eight, hit three century breaks.

Fu did not pot a ball in the opening four frames, with his only five points coming through a foul by his opponent.

O'Sullivan scored a total of 649 points to 35 for Fu in a match which had just an hour and 22 minutes of playing time.

"To be honest with you I'm really struggling. I've got a virus or something, and I feel very dizzy," said O'Sullivan.

"I was just playing off instinct. I thought 'don't stop, don't think, just pot balls'. I've been feeling like that the last five or six days.

"I think it's maybe a lack of magnesium, that's what my nutritionist told me. I've been eating well the last four months and maybe overdone the exercise and made myself a bit ill."

Englishman O'Sullivan will meet Northern Ireland's Mark Allen in the quarter-finals on Thursday (13:00 GMT).

• Full match schedule and BBC television details

Analysis

John Parrott - 1991 world snooker champion

Ronnie has been at his very best today. His focus has been superb.

Every time he has a chance, there's an air of inevitability about it. Marco was just comprehensively outplayed.