The Asp came through Peter Wright, Luke Humphries and Rob Cross to claim the £10,000 winner's bonus in the south west, becoming the third different nightly winner inside five weeks and snapping Michael van Gerwen's three-week streak in the process.
Aspinall recovered from 3-1 down to beat Wright in a hard-fought quarter-final tussle, while he also emphatically stopped a spirited fightback by reigning world champion Luke Humphries in the semis.
The 32-year-old ultimately set up a final showdown against Cross for the Night Five title, with Aspinall defeating the 2018 world champion 6-2 and for the second week in succession to put himself firmly in the play-off mix.
"I was a bit down after the first three weeks, but I've dug deep over the last two nights," Aspinall, a Premier League runner-up in 2020, told the PDC.
"It was a slow start to the season, but last week was massive for myself. That win against Michael Smith has kick-started my season.
"I have been fighting with demons in my own head, but I love this game, and I love the opportunity I've been given.
"Everyone knows I'm a fighter, and I'm over the moon with the win tonight.
"I've not performed at the level I know I’m capable of, but I'm still finding a way to win.
"At the end of the day, we're all in this competition for a reason. I think the standard we're producing week-in, week-out is fantastic, and long may it continue!"
The BetMGM Premier League continues in Brighton next Thursday, as league leader Van Gerwen takes on Night Five runner-up Cross in a battle of the former world champions.
Aspinall faces prodigy Luke Littler in another eye-catching showdown, while Humphries meets Gerwyn Price in a repeat of last year's World Grand Prix final, and Michael Smith plays Wright.
