Whitlock is joined by fellow Aussies Kyle Anderson and Corey Cadby who knocked out top seeds Gary Anderson and Peter Wright respectively.

Some of the world’s best dart players are taking part in the World Series treble header in Australian and New Zealand which moves to Melbourne next weekend followed by Perth

Whitlock hit back from a leg down to lead 2-1 before Harris showed his class with a 12-darter as a 76 finish levelled - but he crucially missed seven darts to lead as the Australian regained the edge.

A 122 finish from Harris saw him respond once more, with Whitlock firing in a stunning 10-darter only to then miss seven doubles of his own as the Kiwi claimed leg eight.

However, double 16 edged Whitlock back ahead, before he took out 60 to seal the win, after Harris missed two darts at tops to force a decider.

"I'm really happy to win," said Whitlock, who now meets Anderson in the quarter-finals. "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.

"I'm really confident at the moment, my darts feel great and I feel like my performance levels are really good at the moment.

"I feel like I can win here. Whether I do or not is another thing, but the belief is there."

He will face Kyle Anderson in a quarter-final on Saturday night. 

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 ten with his fifth 180 before pinning double eight for victory.

Anderson's triumph was followed by another upset as number two 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.

Darts legend Phil Taylor, who is on his farewell tour, defeated New Zealander Darren Herewini 6-4.

Taylor now takes on great rival Van Barneveld in the quarter-finals, after the Dutchman also emerged with a 6-4 win from his tussle with Kiwi veteran Warren Parry.