"I fancied hitting the nine-darter tonight, I told my wife I thought I would do it tonight," said Anderson, who is through to the semi-finals for a third time. "Hitting the nine-darter so early was actually the worst thing I did because it gave me time to think about it and I missed a lot more darts at tops than I normally do.
"Joe played well, he's been playing well for the last few games so it's great to get the win over a top player. Next up it's Jeffrey who has been the player of the tournament for me. Whoever wins this tournament will have to beat him."
The Flying Scotsman ended with an average of 97 compared to Cullen's 95 while he also threw 14 180s (Cullen hit seven) and his checkout percentage was 33.33%.
Anderson remains tournament favourite and will next face Jeffrey de Zwaan, who upset the odds for the third time in a row to defeat Dave Chisnall 16-8 with another stunning display.
The 22-year-old, who began the tournament as a 750/1 outsider, stunned Michael van Gerwen and Adrian Lewis in his previous two encounters and once again proved he's a star in the making by reeling off nine of the final 10 legs to accelerate to continue his dream week in Blackpool.
CLICK HERE FOR MORE FROM JEFFREY DE ZWAAN'S EPIC QUARER-FINAL VICTORY
Thursday July 26
Quarter-Finals (Best of 31 legs)
Friday July 27 (1900 BST)
Quarter-Finals (Best of 31 legs)
TV Channel: Sky Sports
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