Ronnie O’Sullivan and Mark Williams each take command of their quarter-finals

Ronnie O’Sullivan opened up a 6-2 lead over Stephen Maguire in their World Championship quarter-final (Tim Goode/PA)

Ronnie O’Sullivan and Mark Williams took command of their respective quarter-finals on day 11 of the World Championship in Sheffield.

O’Sullivan benefited from an error-strewn display from Stephen Maguire to open up a 6-2 lead following their opening session, with Williams leading Yan Bingtao by the same margin after winning four frames in a row.