Mark Walsh defeated Steve Beaton 6-5 in the final of Championship League Darts' Group Eight to claim the last spot in Thursday's big-money Winners Group.
Walsh has lost in two previous group finals this season but sealed his place alongside the likes of Phil Taylor, Simon Whitlock and Wes Newton with the narrowest of victories over Beaton.
In another dramatic day of action, Dutchman Michael van Gerwen finished at the top of the league table following the round-robin group stage only to lose in the semi-finals - although he did create a piece of history along the way.
Van Gerwen averaged an incredible 121.86 in a 6-0 whitewash of Beaton during the league phase which took only eight minutes and 15 seconds to complete as he restricted the former World Champion to just one dart at a double.
However, Beaton would gain revenge with a superb semi-final display to claim a 6-5 win, finishing 94 on the bullseye to progress to the decider.
Walsh defeated Robert Thornton 6-2 in the other semi-final, with the Scot - who finished second to van Gerwen on leg difference in the league stage after taking six wins from seven games - sharing the first four legs before the Hertfordhire man took four in a row, including an 11-darter, to take victory.
Walsh then overcame Beaton in the tightest of finals which saw the lead change hands three times.
"It's been a very hard week but I've been playing good darts and luckily enough I got through," said Walsh. "I've always got belief in myself that came through. It's very hard in the group games, and (Tuesday) there was only leg difference between going out or being in the semis, so I'm happy with what I've done.
"It's a fantastic tournament and it would be a great title to win on Thursday."