Krzysztof Ratajski won his seventh career PDC title in the space of just two years with an 8-7 victory over Ian White in the Players Championship Four final.
The Polish Eagle, who bagged his first in February 2018 a season before he'd even earned his maiden PDC Tour card, led 7-5 only for Diamond to pull one back before a stunning 155 checkout completed a match-levelling 12-darter.
White was now throwing for glory in Wigan but Ratajski was not to denied and despite agonisingly missing the bullseye for a show-stopping 170 checkout in the decider, he came back to finish the remaining 25 as his opponent waited on 16.
The 43-year-old was in electric form throughout the day, averaging over 103 in four of his six matches en route to the final, including a high of 106.5 in a high-class 6-4 victory over Gabriel Clemens in the last eight.
Ratajski averaged 103.1 when defeating Michael van Gerwen's conqueror Danny Noppert 7-2 in the semi-finals while he also recorded two marks of 104.5 against Nick Kenny, who spurned match darts in a deciding leg, and Robert Collins (6-4).
However, the Pole stunning day could so easily have ended before it even really began, with Mickey Mansell failing to finish from 84 across two visits in the deciding leg of their first-round battle.
His other victim was Vincent van der Voort (6-3) in the third round.
Ratajski, who averaged 98.4 compared to White's 99.6 in the final, collects the first prize of £10,000 which lifts him up to a career-high 18th on the PDC Order of Merit.
Since the start of 2018, only van Gerwen (33), Gary Anderson (9) and Peter Wright (9) have won more titles than him while he's level with Gerwyn Price and James Wade. However, if you only include ranking titles - which all seven of Ratajski's are - then his tally is matched by Anderson and Price, with only MVG's 24 being higher.
The 2017 BDO World Masters winner, who must now look to transfer his immense talents onto the PDC's televised stages, told www.pdc.tv: "When Ian took out 155 it was a terrible moment for me, it made it really hard. This tournament was sometimes lucky for me, I won a few games 6-5 and I survived match darts twice.
"But then I played very well with averages over 100 and I feel very comfortable with the new darts I am playing with. I hope this will be my best season. Last season was brilliant and I hope this one will be even better."
White, who was chasing a 14th career title, had survived three match darts in the deciding leg of a dramatic semi-final with world champion Wright, who averaged 103.8 compared to Diamond's 97.1.
Apart from that - and also being taken the distance by Alan Tabern in the last 32 - the 49-year-old enjoyed a relatively comfortable route to the final, beating Mensur Suljovic (6-3), Jamie Hughes (6-4) and Martin Schindler (6-3) without the need for a 100+ average.
His best statistical performance came in the very first round when recording a mark of 107.6 in a 6-3 triumph over Jan Dekker.
Van Gerwen's 6-4 loss to fellow Dutchman Noppert in the quarter-finals means he's still searching for his first title of 2020 although he did produce a pair of sparkling displays when beating Gary Anderson 6-3 with an average of 107.4 and Ryan Murray 6-2 with a spectacular mark of 110.9.