Barry Lynn became first amateur qualifier ever to reach the UK Open Quarter-Finals after continuing his dream run in Minehead, while Kyle Anderson and Joe Cullen also reached the last eight for the first time in a major championship.
Lynn had won through the Rileys qualifying event held at South Benfleet last month and defeated Dean Stewart, Brett Claydon and Brendan Dolan to progress to Saturday's fourth round.
There he dismantled World Champion Gary Anderson in spectacular fashion, before seeing off Stuart Kellett with another against-the-odds triumph in his first-ever televised tournament appearance.
"It feels great," said Lynn, who sealed his win over Kellett with a 125 bullseye-outer bull-bullseye finish. "It was a struggle against Stuart - it was always going to be a hard match but fatigue set in and my arm felt heavy because it's been a long couple of days.
"I was just glad to scrape over the finishing line. It's been a wonderful weekend so far and I can't wait for Sunday."
Lynn will now get a chance to take on red hot world number one Michael van Gerwen, the reigning UK Open champion, after the Dutch ace came from 2-0 down to win nine successive legs in breezing past Kim Huybrechts.
Van Gerwen had also landed a nine-dart finish in his fourth round win over another Rileys Amateur Qualifier - Rob Cross - earlier on Saturday, and is the 4/11 odds-on favourite to retain his title and claim the £60,000 top prize on Sunday night.
"I'm really pleased to have got through again and even though I wasn't at my best it was enough and I'm happy to be still in for the quarter-finals," said van Gerwen.
"Barry said in an interview earlier on that I was the only player he's scared of, so I'm glad I'm playing him! I need to prepare myself though and I'm looking forward to tomorrow."
The fifth round also saw Australian ace Kyle Anderson book his spot in a first-ever major ranking quarter-final with a clinical 9-2 win over Benito van de Pas - meaning that he has dropped just six legs in seeing off Andy Hamilton, James Wilson and the Dutch youngster so far this weekend.
"I know I can score but I'm hitting doubles and I'm happy with that," said Anderson. "If I can keep improving that then who knows what can happen on Sunday?
"I've been comfortable for a while and I'm feeling confident. I'm on the main stage with a full crowd and I'm looking forward to it."
Anderson will now take on Jelle Klaasen, after the former Lakeside Champion reached the UK Open quarter-finals for the first time by defeating Adrian Lewis 9-7.
Bradford's Joe Cullen will also play in the last four of a TV major for the first time following his 9-7 defeat of 2015 semi-finalist Stephen Bunting.
"Everyone's said I've had the potential for years and I've always known it's been there, and luckily this week it's coming out," said Cullen. "I'm confident and hopefully I'll do well on Sunday."
Cullen drew 2015 runner-up Peter Wright, who enjoyed a 9-5 win over Norwich's Darren Webster as he continued his own bid for a maiden major title.
Five-time UK Open champion Phil Taylor averaged almost 104 as he continued his high-quality weekend in Minehead with a 9-7 win over 2007 finalist Vincent van der Voort, who threatened to force a deciding leg before the Stoke legend finished 81 on the bull to seal victory.
Taylor now meets former Lakeside Champion Mark Webster, after the left-hander reached his fourth major quarter-final in the space of six months with a 9-5 win over Austria's Mensur Suljovic.
The £300,000 'FA Cup of Darts' concludes on Sunday as the action focuses on the Main Stage at the Butlins Minehead Resort, with the quarter-finals in the afternoon session and semi-finals and final in the evening session.
Coral UK Open 2016 Results
Saturday March 5
Joe Cullen 9-7 Stephen Bunting
Phil Taylor 9-7 Vincent van der Voort
Jelle Klaasen 9-7 Adrian Lewis
Michael van Gerwen 9-2 Kim Huybrechts
Mark Webster 9-5 Mensur Suljovic
Barry Lynn 9-5 Stuart Kellett
Peter Wright 9-5 Darren Webster
Kyle Anderson 9-2 Benito van de Pas