Selby won the British title for the first time in February
Essex's Daryl Selby edged a marathon match against Surrey's Tom Richards to reach the quarter-finals of the Canary Wharf Classic in London.
Selby won in five games, 11-13 11-9 11-7 14-16 11-9.
He will now play Sheffield's world number one Nick Matthew, who he beat in the British final in February.
London's Peter Barker, Leeds' James Willstrop and Somerset's Joey Barrington are the other three Englishmen through to the last eight.
Barrington and Wilstrop play each other in one of two all-English quarter-finals, while Barker is up against Australia's Stewart Boswell.
Germany's Simon Rosner meets Frenchman Gregory Gaultier in the final last-eight tie.