Unheralded American Sam Stevens grabbed the early clubhouse lead in Thursday's first round of the US Open with Rory McIlroy and Ludvig Aberg only one stroke adrift.
Gusting winds under overcast skies at Shinnecock combined with thick rough and greens slightly softened by watering to baffle the world's top golfers.
Stevens, who has never won a PGA Tour event, sank a birdie putt from just outside six feet at the ninth hole, his last of the day, to fire a two-under par 68.
The 29-year-old Texan, in only his eighth major start, began with a double bogey at 10, waited through a two-hour fog delay then solved Shinnecock for six birdies against two bogeys.
"Got off to a weird start but made a birdie on the very next hole. Felt like I settled in after that," Stevens said.
"Drove the ball well. Hit my irons really well. Had a lot of birdie looks. The greens were a little bit softer. They had to water them. Made a few nice putts."
American amateur Ryder Cowan was at two-under through five holes.
McIlroy, another back-nine starter, closed with back-to-back bogeys after making an 11-foot eagle putt on the par-five fifth to shoot 69 and share second in the clubhouse with Sweden's Aberg and Americans Max Greyserman and Brian Harman.
"Overall, a really good day," McIlroy said. "Obviously it stings a little bit to finish the way that I did, especially not feeling like I hit particularly bad iron shots on eight and nine there."
McIlroy, who won his sixth career major at the Masters in April, stayed patient in tough conditions.
"It was obviously a really tricky day and just a day to stay patient and hang in there, and I hit enough good shots to give myself some chances," he said. "I think anything in red figures today was a good effort."
Second-ranked McIlroy could become just the seventh player to capture the Masters and US Open in the same year, the first since Jordan Spieth in 2015.
Aberg, a back-nine starter chasing his first major title, sank a birdie putt from just inside 30 feet to briefly lead but fell back after a bogey at the fourth after finding the left rough.
"The wind is definitely a big factor," Aberg said. "Pleased with the way I was hitting it, pleased with the way I was scrambling when I had to. Yeah, it's a tough test."
A field of 156 chased a record top prize of $4.5 million from a record $22.5 million purse.
Organizers kept green speeds below maximum and watered greens between waves to help balls stay on the putting surfaces amid the gusting winds.
In the 2004 and 2018 US Opens at Shinnecock, brutal winds and high green speeds had groundskeepers watering greens between groups in a bid to keep the course playable, many complaining that organizers had "lost the course."
SCOTT'S RUN HITS 100
Adam Scott, the 2013 Masters winner, made his 100th consecutive major start, joining Jack Nicklaus with 146 in a row as the only men to reach the milestone. The 45-year-old Australian fired a 73.
Top-ranked Scottie Scheffler, seeking a victory to complete a career Grand Slam, shot 72.
The two-time Masters winner won captured last year's British Open and PGA Championship to give himself a first chance at the career Slam at Shinnecock on Sunday, his 30th birthday.
Brooks Koepka, chasing his sixth major title on the same course where he won the 2018 US Open, fired a 73.
"Conditions were tough," Koepka said. "It's just weird how soft the greens are. I understand why they're soft. Not complaining. It's just a difficult day."
The 36-year-old American is fighting an ulnar nerve issue that numbed his left ring finger and pinky and forced him to withdraw from last week's PGA Canadian Open.
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