GIANT-KILLER Keegan Brown's dream debut at the SINGHA Beer Grand Slam of Darts saw him knock out 2012 champion Raymond van Barneveld with a brilliant 10-7 win on Wednesday.

The 22-year-old from the Isle of Wight had defeated world number three Adrian Lewis as well as Austrian youngster Rowby-John Rodriguez as he qualified through the Group Stage at the Wolves Civic.

And Brown - a medical lab assistant in blood services at St Mary's Hospital on the Isle of Wight who has taken holiday to compete in Wolverhampton this week - won through to the quarter-finals with a superb win over the 2012 Grand Slam champion.

Brown, the World Youth Champion, left the Dutchman reeling by taking the opening four legs without reply, hitting three 180s and a 121 finish as he moved 4-0 up.

Van Barneveld pulled back to 5-2 and then took out 106 as he reduced the gap to 7-3 - only for Brown to finish double eight and double 18 to move to the brink of the win.

The game took a dramatic twist as Brown missed five match darts in the next four legs, with van Barneveld showing his class with finishes of 72, double five, 70 and 125 to pull back to 9-7.

Three missed darts from the Dutchman at double four in the next, though, proved crucial as Brown took out 122 on the bull to finally close out the biggest win of his career.

"I'm absolutely over the moon," said Brown, who is guaranteed a career-best £15,000 prize money. "To reach the last eight of my first big TV tournament is amazing.

"If someone said to me that I'd beat Adrian in the group stage then I'd have ripped their arm off, so to follow that up with a win over Barney in the last 16 is something that I can't describe.

"Raymond's a Premier League player so you know that you've got to bring your best game otherwise you don't stand a chance, and I did that tonight.

"Raymond's a big idol of mine, so I'm just so happy to beat him and I'm looking forward to tasting this atmosphere again in the quarter-finals. Everything's a bonus for me and it's been a huge learning curve for me this week."

Brown now takes on Dave Chisnall in Friday's quarter-finals, with the St Helens thrower having defeated Robbie Green 10-3 earlier in the night.

Checkouts of 136 and 125 helped Chisnall to take charge of the game as he won the opening five legs without reply before Green finished 88 on the bull and double eight to hit back.

Another three successive legs helped Chisnall move 8-2 up, and though Green landed another bullseye finish, the St Helens man took the next two to seal his first Grand Slam quarter-final.

"I've known Robbie for a long time and it's always a hard game against him, but he missed a few doubles early on and I took advantage," said Chisnall.

"I've been playing well and my doubles have been very good so far this week. I want to improve my scoring a little bit - but I'd rather hit a double than a treble!

"I think I can win this. I'm feeling comfortable and if I can have a bit of luck on the way through I could carry this on."