Simon Whitlock knocked Adrian Lewis out of the McCoy's Premier League with a thrilling comeback from 5-2 down to win 8-6 and end the world champion's hopes of claiming a play-off place.
Lewis had to secure victory to be assured of keeping alive his hopes of going one better than last year in this competition but slipped to defeat against the clinical Australian.
The pair traded 180s in sharing the opening two legs, with Lewis hitting tops for a 13-darter to make a flying start before Whitlock finished 92.
'Jackpot' then stretched into a 4-1 lead and after another exchange of legs, including a 130 finish from the Australian, he looked well set at 5-2.
Lewis then opened the eighth leg with five successive treble 20s, hitting a 180 and 123, but a 14-darter from Whitlock sparked him back into life.
Lewis looked to have steadied things when he regained the lead at 6-5, but 'The Wizard' won three straight legs - including an eyecatching 140 finish along the way - to send the world champion spinning out.
Whitlock told Sky Sports 1: "I was already in the semi-finals but wanted to win tonight to make sure that I avoided Phil Taylor in the semi-finals so I'm over the moon to have done that."
Andy Hamilton will face Whitlock in next week's play-offs after booking his place in the last four thanks to an 8-1 hammering of fellow pre-tournament outsider Kevin Painter.
'The Hammer' opened the match with the first of four 180s and ground his way to an ultimately facile victory against a disappointing Painter.
'The Artist' never really recovered from missing doubles in the opening two legs and though he plundered a 111 finish in leg five, he was short of his best.
Victory completed a remarkable fightback from 'The Hammer'; the Stoke thrower sat bottom of the eight-man table halfway through the competition.
James Wade claimed the final place in the play-offs after a thrilling 7-7 draw against Raymond van Barneveld.
Van Barneveld had to win the match to finish in the top four and led 4-2 at one stage before Wade struck back with four successive legs to lead 6-4.
The rollercoaster nature of the match continued as 'Barney' moved 7-6 up and to the brink of the play-offs but Wade hit a 180 in a 13-dart final leg to claim the draw he needed to set up a showdown with Phil Taylor next week.
'The Power' finished the regular season with a 7-7 draw against Gary Anderson in the last match of the night.
Taylor said: "I wanted to get a win and hit a massive average but it wasn't to be - it was a bit like a sparring session ahead of the play-offs.
"I know I'm in for a tough game and I'll be getting ready for James. When I beat him in the final, I won 10-8 and hit two nine-darters because he's such a good player that I know what he'll do."
Wade said: "It was a hard game and Raymond played well, so there's a massive sense of satisfaction to be in the play-offs again.
"I'm looking forward to playing Phil in the semi-finals. He seems to do something special against me every time we play so I know the size of the task, but I'm being positive about it."