Phil Taylor and Michael van Gerwen remain on course to face each other in the final of the PDC World Championship.
Taylor progressed to the quarter-finals on Sunday evening with a 4-0 win over Robert Thornton.
The Power will meet Andy Hamilton in the last eight, after last year's runner-up beat Terry Jenkins 4-1.
Earlier in the day, second seed Van Gerwen became the final player to reach round three, when he came from two sets down to beat Peter Wright 4-2.
Mark Walsh averaged 91.41 as he beat Justin Pipe 4-2 to set up a last 16 meeting with Wes Newton.
World number three James Wade overcame Steve Beaton 4-2 and will now face Vincent van der Voort, who beat Dean Winstanley by the same scoreline, despite the Yorkshireman becoming just the third player to hit a nine-darter at Alexandra Palace.
