Cullen ended the match in style with a 104 finish for a 12-dart leg. The Bradford Ace produced a 98 average and made six out of seven successful attempts on the doubles.
Ricky Evans overcame William O'Connor, who beat Michael van Gerwen on Saturday evening. Ritchie Edhouse booked his place for the last eight after edging out Ross Smith.
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Afternoon Session (1pm local time, 12pm BST)
William O'Connor (86.53) 2-6 (90.32) Ricky Evans
Joe Cullen (98.60) 6-4 (97.70) Daryl Gurney
Ritchie Edhouse (93.71) 6-2 (90.10) Ross Smith
14:30 Kyle Anderson v Jeffrey de Graaf
15:00 Peter Wright v Dave Chisnall
15:30 Simon Whitlock v Darren Johnson
16:00 Adrian Lewis v Josh Payne
16:30 Ian White v Mervyn King
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