Luke Littler and Luke Humphries booked passage through to the US Darts Masters quarter-finals, but Josh Rock crashed out in a stunning defeat to Jim Long.
Long's reward will be a showdown against Littler, after the world No 1 survived an early scare to defeat a tenacious David Cameron.
Littler was nowhere near his blistering best in the early exchanges, although he duly found his range to avoid the upset, overturning a 4-3 deficit with the aid of five maximums.
Long memorably defeated Michael Smith at the US Darts Masters back in 2023, and the Canadian veteran produced another big upset in the Big Apple, running out a 6-4 winner against a profligate Rock.
The Northern Irishman recovered from a sluggish start to restore parity at three apiece, only for Long to win three of the next four legs and complete the upset.
"It's an amazing feeling to win on this stage. I'm over the moon," reflected Long - making his fourth US Darts Masters appearance.
"I've played Josh three times on the tour so we're familiar with each other, and I was fortunate he missed a couple of doubles at the end there.
"I just want to play every game I can play and perform at my best with every chance I get."
Reigning champion Humphries also took centre stage on Day One, dispatching former North American champion Leonard Gates 6-1 to begin his bid for back-to-back titles in New York.
"This is a really prestigious event and one of the best venues in the world," declared the world No 2.
"My brother told me in the last eight events I've played in - including the Premier League - I've made eight finals on the trot, so that's given me a lot of confidence.
"I've been a really tough player to beat in the last few weeks, and it's nice to have that winning feeling back."
Humphries' next assignment will be a tie against Stephen Bunting, who swept aside a struggling Alex Spellman 6-2 to register his first victory on the iconic Madison Square Garden stage.
Dutch No 1 Gian van Veen was another comfortable winner on Thursday night, marking his US Darts Masters debut with a crushing 6-1 victory against big stage newcomer Fred Krueger.
Jonny Clayton now awaits the European Champion in a blockbuster quarter-final tussle, after the Welsh No 1 delivered a perfect doubling display in his 6-2 thumping of Gary Mawson, averaging almost 99 in the process.
Gerwyn Price and James Wade will also lock horns in the quarter-finals, following hard-fought wins over Brayden Hall and Adam Sevada respectively.
2024 runner-up Price overcome Canadian prospect Hall 6-4 in his opener, while Wade enjoyed a winning return to World Series action, following a 6-3 success against American number one Sevada.
The US Darts Masters will conclude on Friday evening, as the quarter-finals, semi-finals and final are held in front of a sell-out crowd of 5,000 fans - a record for darts in the US.
Thursday June 25
Round One
Gian van Veen 6-1 Fred Krueger
Gerwyn Price 6-4 Brayden Hall
James Wade 6-3 Adam Sevada
Jim Long 6-4 Josh Rock
Luke Littler 6-4 David Cameron
Luke Humphries 6-1 Leonard Gates
Jonny Clayton 6-2 Gary Mawson
Stephen Bunting 6-2 Alex Spellman
Quarter-Finals
Luke Littler vs Jim Long
Gerwyn Price vs James Wade
Luke Humphries v Stephen Bunting
Gian van Veen vs Jonny Clayton
Best of 11 legs
Semi-Finals
Littler/Long vs Price/Wade
Humphries/Bunting vs Van Veen/Clayton
Best of 13 legs
Final
v
Best of 15 legs
The 2026 Betfred World Matchplay will take place at the iconic Winter Gardens from July 18-26, as a 32-player field compete for the prestigious Phil Taylor Trophy.
World No 1 Luke Littler will be eyeing back-to-back titles in Blackpool, with 2024 champion Luke Humphries and three-time World Matchplay winner Michael van Gerwen also set to star in the £1m event.
This summer's action will also feature the fifth staging of the Betfred Women's World Matchplay, as eight of the biggest names in the women's game battle it out for the title currently occupied by Lisa Ashton.
Who will win this year's World Matchplay Darts? Luke Littler will be defending his title and you can watch all the action on Your Site. .
