STEVE WEST ended Michael van Gerwen's reign as Unibet European Champion with the performance of his career in a 10-7 win, as Peter Wright, Daryl Gurney and Mensur Suljovic also exited the event.
Van Gerwen was aiming to claim a fifth straight European Championship win, but saw West hold his nerve in a thriller to match his famous win over Phil Taylor at the 2016 World Grand Prix with another memorable triumph.
West led 4-1 before Van Gerwen levelled after ten legs, but three in a row - using just 36 darts - moved the world number 26 clear before he held on for a first career win over the Dutchman.
"I can't describe the feeling," said West. "Unfortunately Michael didn't play his best game, but I took my chances.
"Beating Phil Taylor was huge for my career and gave me a lot more confidence, but this is one of the best wins ever because Michael is the best player in the world.
"To beat him is a triumph. I need to up my game a bit more because a 96 average won't win me the title, but tonight I took my chances when I needed to."
West now faces a quarter-final on Sunday against Simon Whitlock, the 2012 European Championship winner who kept alive his hopes of a second title by seeing off Peter Wright 10-6.
The pair shared the opening four legs before Whitlock pulled clear to lead 5-2, including a 14-darter to break throw, and 8-4.
Wright took out 71 and 58 to respond, but any hopes of a fightback were ended in clinical fashion as the Australian powered home checkouts of 136 and 101 to march into Sunday's quarter-finals.
"Peter is the second best player on the planet at the moment so I'm happy with the win but he wasn't at his best tonight," said Whitlock.
"He didn't hit a 180 and that's not Peter. I wasn't great either but I did enough to get the win.
"I've won this event before and I believe I can win it again but I've got to improve. I have to sharpen my game up for Sunday."
World Champion Rob Cross powered into the last eight with a dominant 10-2 win over Richard North as he continued a bid to reach the European Championship final for a second successive year.
Cross took out a 142 finish on his way into a 4-1 lead, before reeling off six straight legs to seal a comfortable win.
"I was confident tonight and I was practising well but I wasn't punished and Richard didn't take his chances," said Cross.
"I'm feeling alright but I can get better and I'm just happy to get through to the next round."
Cross will now meet Joe Cullen, who won through to his second televised quarter-final of 2018 with a dominant 10-4 defeat of Michael Smith.
The Yorkshireman had also reached the last eight of July's World Matchplay, and continued that form to capitalise on a below-par showing from Smith.
The Shanghai Darts Masters winner missed 17 darts at doubles in the opening four legs as Cullen took command, only for Smith to hit back to 5-4.
However, he was unable to level as Cullen earned breathing space once again before landing legs of 14 and 11 darts to pull clear before sealing the win with a 132 bull finish.
📽 "I thought I was three darts ahead of Mike the whole way through the game..."— PDC Darts (@OfficialPDC) October 26, 2018
After claiming a 10-4 win over Michael Smith, @Rockstar_13_ is looking forward to the @Unibet European Championship quarter-finals.#Unibet180 pic.twitter.com/BSlxdCV0vM
"It was a good performance," said Cullen. "I thought I was three darts ahead of Mike the whole way through the game - he wasn't himself and he'll be disappointed with his performance.
"I wanted to stay on top of him and capitalise on his errors. I think I scored well when I needed to."
Earlier, 2016 European Championship finalist Suljovic and world number five Gurney exited the tournament as the first round concluded in Friday's afternoon session.
2016 finalist Suljovic was knocked out in the first round as Spain's Cristo Reyes enjoyed a 6-3 win.
Reyes pulled into leads of 4-1 and 5-2 thanks to some clinical finishing, which included an 84 finish of bull and double 17, before a 93 checkout sealed a big win.
Chisnall produced a brilliant 157 checkout in the deciding leg of his contest with Adrian Lewis to move into the last 16.
Former champion Lewis had held a narrow 5-4 lead as a tight contest moved towards its culmination, but he crucially missed one match dart at tops in the tenth leg before Chisnall levelled and then edged the decider.
WHAT. A. FINISH.— PDC Darts (@OfficialPDC) October 26, 2018
Chizzy pulls out a stunning 157 to beat Adrian Lewis 6-5 - an incredible way to end the afternoon session! pic.twitter.com/iTcLvOFTLc
Former World Grand Prix winner Gurney saw his European Championship hopes ended by Ricky Evans as the Kettering ace enjoyed a 6-4 success.
A fine start from Gurney, a semi-finalist last year, saw him land back-to-back 14-darters to take leads of 3-1 and 4-2.
Evans hit back in the seventh and broke throw to level, before punishing missed doubles from Gurney in the next two to seal his second round place.
"I'm overwhelmed to beat a player of Daryl's quality," said Evans, a European Tour finalist in September. "I didn't start well but getting back to 3-2 at the break was important.
"Just to be here means so much to me and I'm loving my darts at the moment."
Evans will now face James Wade, after the new father began his challenge for a first TV title in almost four years by defeating German youngster Martin Schindler 6-3.
The left-hander took command by claiming the opening three legs without reply, and held on to the advantage as he moved through to the last 16.
"It wasn't exceptional," said Wade. "I was steady and I was lucky enough to prevail."
Wade, whose wife Sammi gave birth to baby Arthur a week last Monday, added: "I'm the happiest man in the world to have a newborn baby boy
"He's the best thing that's ever happened to me. I'll do my best here and it's not easy being away. I know how good I am on the dartboard - but now I've got someone to do it for."
Max Hopp delighted the German crowd at the Westfalenhalle with a dominant 6-1 win over Ireland's William O'Connor as he set up a second round tie with James Wilson.
Hopp opened the game with a 164 finish and led 3-0 before O'Connor took out 64 to briefly silence the home support, but the former World Youth Champion claimed a key fifth before completing the win.
Hopp will now meet James Wilson, who impressed with an outstanding 103.64 average as he swept past Austrian Darts Open winner Jonny Clayton 6-2 in their first round tie to open Friday's double session.
Wilson raced into a five-leg lead, hitting five doubles from six attempts, and though Wilson hit back to capitalise on missed doubles in the next two legs, an 80 finish moved the Yorkshireman into the last 16.
"It's a massive win," said Wilson. "You know when you're playing Jonny that you've got to play well. You've got to get on top of him and thankfully I did.
"He clawed it back a bit but I'm happy with my performance. The European Tour has been great for my confidence this year and it's been a big boost. I think I'm getting more consistent."
Darren Webster out-lasted Stephen Bunting in an 11-leg thriller to secure his second round spot in Dortmund with a narrow 6-5 triumph.
A 121 finish helped Webster into a 3-1 lead before Bunting hit back by taking out 116, and the former Lakeside Champion also capitalised when his opponent burst an attempted 142 finish in leg seven.
However, it was Webster who was stronger as the game went to a decider, landing a 180 before taking out double 12 for a 14-darter to set up a tie with Reyes.
"I'm delighted," said Webster, who averaged over 99. "I kept hitting him with everything and he kept coming back, but the last leg was good.
"I'm a fighter and I'm starting to produce it on the big stage. I'm loving every minute of it."
Gerwyn Price defied a 101 average from Kyle Anderson to move into the last 16 with a 6-4 defeat of the 2017 semi-finalist.
Winning legs of 13, 14 and 13 darts helped Anderson into an early 3-2 lead and he also took out 100, only to see Price claim the crucial first break of throw in leg nine with a 12-darter as he followed a 180 with an 86 finish.
Price then held throw to seal his spot in round two, and admitted: "It was a tough game and it felt like I was always playing catch-up.
"Kyle was better than me but I've learned how to grind out games and I broke him at the right time before holding on in the last leg."
The second round concludes on Saturday evening, beginning with Price up against Chisnall before Reyes meets Webster, while Wade takes on Evans and Hopp meets Wilson.
The £400,000 tournament then concludes on Sunday with the quarter-finals, semi-finals and final at the Westfalenhalle.
Following Friday's drama in Dortmund, World Champion Cross has been installed as Unibet's new 2/1 favourite to lift the title on Sunday night.
Whitlock is the 6/1 second favourite, with Wade 13/2 as he aims to claim a first TV title for almost four years ahead of Chisnall (8/1), Price and Cullen (both 10/1).
The Unibet European Championship is screened live on ITV4 and through the PDC's worldwide broadcast partners.
2018 Unibet European Championship
Friday October 26
First Round x8
James Wilson 6-2 Jonny Clayton
Darren Webster 6-5 Stephen Bunting
Gerwyn Price 6-4 Kyle Anderson
Cristo Reyes 6-3 Mensur Suljovic
Ricky Evans 6-4 Daryl Gurney
Max Hopp 6-1 William O'Connor
James Wade 6-3 Martin Schindler
Dave Chisnall 6-5 Adrian Lewis
Evening Session (2000 local time, 1900 UK time)
Second Round x4
Joe Cullen 10-4 Michael Smith
Simon Whitlock 10-6 Peter Wright
Rob Cross 10-2 Richard North
Steve West 10-7 Michael van Gerwen
Saturday October 28 (2000 local time, 1900 UK time)
Gerwyn Price v Dave Chisnall
Cristo Reyes v Darren Webster
James Wade v Ricky Evans
Max Hopp v James Wilson
Sunday October 28
Afternoon Session (1.45pm local time, 12.45pm UK time)
Quarter-Finals - Order of Play TBC
Steve West v Simon Whitlock
Joe Cullen v Rob Cross
Reyes/Webster v Hopp/Wilson
Wade/Evans v Price/Chisnall
2/1 Rob Cross
6/1 Simon Whitlock
13/2 James Wade
8/1 Dave Chisnall
10/1 Gerwyn Price
10/1 Joe Cullen
12/1 Darren Webster
14/1 Steve West
16/1 James Wilson
20/1 Cristo Reyes
25/1 Max Hopp
33/1 Ricky Evans
Saturday Evening Match Odds
13/10 Gerwyn Price v Dave Chisnall 8/13
8/5 Cristo Reyes v Darren Webster 1/2
4/9 James Wade v Ricky Evans 9/5
11/10 Max Hopp v James Wilson 8/11
Odds courtesy www.unibet.co.uk.