Top seeds Gary Anderson and Peter Wright crashed out of the Auckland Darts Masters on the opening night as Australian pair Kyle Anderson and Corey Cadby showed their class at the Trusts Arena in west Auckland.
World No 2 Anderson had gone all the way to glory in Auckland last year and had been aiming to follow up his repeat success from the Dubai Darts Masters by retaining the title on his return to the Trusts Arena.
However, Australian star Anderson produced a brilliant display to average almost 103 and hit five 180s in a thrilling 6-4 win over the Scot as he ended his namesake's title defence at the first hurdle.
After the pair traded 180s in the opening leg, Gary Anderson took out 138 to lead, only to see the Australian power through the next three for a 3-1 advantage.
A 14-darter and a 100 finish for a 12-dart leg helped Gary Anderson to win three of the next five as he stayed in contention, but Kyle Anderson opened leg 10 with his fifth 180 before pinning double eight for victory.
Having won his maiden PDC ranking title last week, where he also hit a nine-darter, Anderson admitted that his confidence is high as he bids for glory in Auckland.
"I'm delighted," said the 29-year-old. "I couldn't hit a thing in the practice room but as soon as I got on stage everything started to flow, which is a really good sign.
"It's going well on the ProTour and it was just a case of hitting the doubles on stage, and today that happened for me. I'm taking everything seriously and things are starting to go my way."
Anderson's triumph was followed by another upset as No 2 seed Peter Wright, the reigning UK Open champion, was eliminated with a 6-4 defeat to inspired Corey Cadby.
Cadby had stunned Phil Taylor in the Perth Darts Masters in only his second televised appearance last year before losing out to Wright - but the world youth champion gained revenge with the aid of six 180s.
Each of those maximums came in the opening six legs, as Wright withstood a barrage of big scores to remain level at three-all - despite his own trouble hitting the treble 20 leading to a mid-game switch to the 19 bed instead.
That paid off as Wright hit a 13-darter in leg seven to lead 4-3, but Cadby levelled, took out a superb 112 finish to regain the lead and then finished double 16 for a memorable triumph.
"I wanted revenge against Peter and I got it," said Tasmania-born Cadby. "My dad told me to never let someone beat you twice in a row and I managed to stop Peter doing that tonight.
"I'm not here to lose and I know I can beat the best on my day. We'll see what happens but I don't plan on losing."
Simon Whitlock completed a trio of Australians to progress to the quarterfinals on the opening night despite being given a stern test by New Zealand's Cody Harris, who eventually fell to a 6-4 defeat.
"I'm really happy to win," said Whitlock, who now meets Anderson in the quarterfinals. "He played well and every time I gave him a chance he seemed to take it, but there's a lot more to come from me."
The other three New Zealanders in the PDC World Series of Darts event joined Harris in being eliminated on the opening night, although debutant Darren Herewini and veteran star Warren Parry both gave their world champion opponents a scare.
Herewini, a 25-year-old from Porirua who won through last weekend's DPNZ Qualifiers, pushed the legendary Phil Taylor all the way on his first TV appearance before the 56-year-old edged through with a 6-4 win.
Taylor had looked set to pull away when, after sharing the opening two legs, he took out 101 and an 11-darter to move into a 3-1 lead.
Taylor now takes on great rival Van Barneveld in the quarterfinals, after the Dutchman also emerged with a 6-4 win from his tussle with Invercargill's Parry.
Parry - who knocked out Michael van Gerwen in the Sydney Darts Masters three years ago - shared the opening six legs with the Dutchman as he chased another upset win, twice capitalising on missed doubles from Van Barneveld as well as finishing 107.
Michael Smith impressed on his World Series of Darts debut with a 6-0 whitewash of Rob Szabo, averaging 103.66 and hitting four 180s as he set up a mouth-watering tie with Cadby.
James Wade battled his way to a 6-2 win as he overcame New Zealand's Mark Cleaver, who lost out in the first round for the second time in three years.
FIRST ROUND RESULTS
Michael Smith 6-0 Rob Szabo
Daryl Gurney 6-2 Rob Modra
James Wade 6-2 Mark Cleaver
Raymond van Barneveld 6-4 Warren Parry
Phil Taylor 6-4 Darren Herewini
Simon Whitlock 6-4 Cody Harris
Gary Anderson 4-6 Kyle Anderson
Peter Wright 4-6 Corey Cadby
All games best of 11 legs
QUARTERFINALS (best of 19 legs)
James Wade v Daryl Gurney
Kyle Anderson v Simon Whitlock
Raymond van Barneveld v Phil Taylor
Corey Cadby v Michael Smith