Rising Dutch star Jelle Klaasen defeated top seed Mervyn King in the second round of the Lakeside World Championship in Frimley Green.
The 21-year-old Dutchman lost the first set but hit back to win 4-2.
"I didn't expect anything from the match. I just wanted to show my best and I did. Maybe I can go on and win the tournament now," said Klaasen.
England's Paul Hogan prevented a Dutch double as he beat Albertino Essers 4-2 later on Tuesday.
After losing the first set Klaasen, who has only been playing the game for five years, reeled off the next three sets.
There was a brief revival from King as he took four consecutive legs to reduce the arrears to 3-2, but Klaasen kept his nerve and went through with his second dart at double top.
King, who also went out in the second round to a little-known Dutchman last year, was generous in defeat.
"I hit too many singles and not enough trebles," said King.
"I didn't play as well as I can and a few loose darts cost me, but the lad was brilliant. He was better than me, it's as simple as that."
Shaun Greatbatch added his name to the list of potential unseeded finalists when he beat Denmark's Per Laursen 4-2.