Michael van Gerwen suffered a shock defeat to Ross Smith on a dramatic opening night of the 2019 Unibet European Championship which also saw reigning champion James Wade knocked out by Jonny Clayton.
Having lifted the World Grand Prix and Champions League titles in back-to-back weekends, top seed Van Gerwen came into the tournament as a red-hot favourite to land a fifth European Championship title in six years in Göttingen.
However his plans were derailed by Smith, who produced one of the finest performances of his career, holding his nerve to come through a last-leg decider and claim a famous 6-5 victory.
"Never in a million years did I think I'd be experiencing a night like this from where I was a couple of years ago," said Smith, who took a break from the sport in 2017.
"I made the decision to just keep on going with my career in darts and tonight it all came together.
"I've been preparing for this game for two weeks in my outdoor cabin, just focussing on playing the board rather than Michael.
"If you play Michael you lose, it's as simple as that. He's the best player in the world by a mile so if you start thinking about beating him then you won't.
"You've just got to play the dartboard and that's what I did tonight. I showed everyone how well I know I can play."
With both players averaging over 110 at 3-3, Smith threw a 14-dart leg to hit the front for the first time and go within touching distance of a huge upset.
Van Gerwen kept his cool exterior and kept up his usual high standard to take the match to a deciding leg.
With the world number one waiting on 88, Smith produced a stunning 114 checkout when he needed it most to seal his first ever win against Van Gerwen.
An unpredictable night also saw Wade's reign as European Champion ended by Welshman Clayton, who produced a scintillating display to whitewash Wade 6-0.
A dominant display from Clayton saw him end the contest with a 111.33 average, hitting six doubles from eight attempts to become the first player in the tournament's history to knock out the reigning champion in round one.
"I know I've got the game, it's just about being consistent and confidence is key in darts," Clayton explained.
"I'm so happy with how I played tonight, it's a massive step in the right direction for me.
"I knew what I had to do and it went well. I know James didn't play to his best at all but that's when you've got to take your chances and that's what I did."
Simon Whitlock proved too strong for Adrian Lewis in the battle of the former European Champions, averaging just under 100 in a convincing 6-1 win.
Dave Chisnall and Joe Cullen also impressed in their victories against Dimitri Van den Bergh and Mervyn King respectively, while Rob Cross sealed his passage to round two in style with a 154 checkout to end Darren Webster's fightback.
Daryl Gurney claimed a hard-fought 6-4 win over William O'Connor in the final game of the evening and Ricky Evans survived two match darts to make it a Unibet European Championship debut to forget for Glen Durrant with a 6-5 triumph over the World Matchplay semi-finalist.
Friday will see the remaining eight first round games take place in the afternoon session, before Thursday's winners return to the stage in the evening session for the start of round two.
Thursday October 24
Evening Session
First Round
Joe Cullen 6-2 Mervyn King
Dave Chisnall 6-3 Dimitri Van den Bergh
Ricky Evans 6-5 Glen Durrant
Simon Whitlock 6-1 Adrian Lewis
Rob Cross 6-3 Darren Webster
Jonny Clayton 6-0 James Wade
Ross Smith 6-5 Michael van Gerwen
Daryl Gurney 6-4 William O'Connor
Friday October 25
Afternoon Session (1245 local time, 1145 BST)
First Round
Jamie Hughes v Jermaine Wattimena
Keegan Brown v Stephen Bunting
Krzysztof Ratajski v Chris Dobey
Nathan Aspinall v Steve Beaton
Mensur Suljovic v Vincent van der Voort
Ian White v Michael Smith
Peter Wright v Jeffrey de Zwaan
Gerwyn Price v Ted Evetts
Evening Session (1900 local time, 1800 BST)
Second Round
Joe Cullen v Rob Cross
Daryl Gurney v Simon Whitlock
Dave Chisnall v Jonny Clayton
Ross Smith v Ricky Evans
Saturday October 26
Evening Session (1900 local time, 1800 BST)
Second Round
Suljovic/Van der Voort v Ratajski/Dobey
White/M Smith v Brown/Bunting
Price/Evetts v Aspinall/Beaton
Wright/De Zwaan v Hughes/Wattimena
Sunday October 27 (1245 local time, 1145 BST)
Afternoon Session
Quarter-Finals
Evening Session (1900 local time, 1800 GMT)
Semi-Finals & Final