The US Open has been suspended for the day because of lightning storms with outsider Andrew Landry leading by one shot at Oakmont Country Club.
Nine players had completed their first rounds when play was halted at 21:34 BST with American world number 624 Landry on three under after 17 holes.
Two-time Masters winner Bubba Watson is joint second on two under, while England’s Lee Westwood is one under.
Rory McIlroy is three over par after 12 and Jordan Spieth is one over after 11.
Spieth, the defending champion, started his round on the 10th and had a birdie on the par-five 12th, but gave that shot back with a bogey on the 14th.
The American world number two and his playing partners Bryson DeChambeau and reigning Open champion Zach Johnson had been warned by a rules official to pick up their pace of play as they left the 16th tee.
Westwood in contention
Westwood, who also started on the 10th, holed a 124-yard wedge shot for an eagle on the par-four 15th, but missed a three-foot birdie putt on the 17th as he completed his first nine holes in two under.
Bogeys on the first and second saw Westwood drop back to level par but he birdied the par-five fourth before play was halted for a third time at 20:51 BST.
“It’s frustrating having to keep coming off but there’s nothing you can do about the weather,” he said.
“I’m playing well though, playing nicely. I’ve dropped shots when I’ve missed it in the wrong spots and made some nice birdies too.”
The former world number one made use of the first rain delay to watch England beat Wales 2-1 at Euro 2016, while 2011 champion McIlroy left the course in a hurry after the hooter ended play for a second time so he could watch Northern Ireland beat Ukraine 2-0.
American amateur Scottie Scheffler, 19, is the clubhouse leader after shooting a one-under-par 69.
However, 28-year-old qualifier Landry will return on Friday with a 10-foot putt for birdie on the ninth, his last hole, to move to four under.
Only half of the 156-strong field were able to start their first rounds and among those to stay in the clubhouse were world number one Jason Day, six-time runner-up Phil Mickelson and England’s 2013 US Open champion Justin Rose.