|US Open first-round leaderboard|
|-5 J Thomas (US); -4 P Reed (US), M Wolff (US), T Pieters (Bel); -3 R McIlroy (NI), L Westwood (Eng), L Oosthuizen (SA);|
|Selected: -1 J Rahm (Spa), B DeChambeau (US); E M Wallace (Eng); +1 A Sullivan (Eng); +3 J Rose (Eng), D Johnson (US), T Woods (US); +4 T Hatton (Eng), T Fleetwood (Eng), R MacIntyre (Sco); +9 P Mickelson (US)|
Rory McIlroy and Lee Westwood sit two strokes off the first-round lead at the US Open as American Justin Thomas set the early pace in New York.
Former champion McIlroy, of Northern Ireland, and England's former world number one Lee Westwood both shot 67 at an unusually benign Winged Foot.
Thomas birdied the 18th to go one clear of Belgian Thomas Pieters and Patrick Reed and Matthew Wolff of the US.
Reed had a hole-in-one at the par-three seventh, as did Will Zalatoris in a 70.
Zalatoris almost holed his second ace of the round at the par-three 13th but his ball hit the flagstick and rolled a couple of feet away.
In the previous five US Opens held at Winged Foot, there had been only two holes-in-one.
Pieters and Wolff joined former Masters champion Reed at four under after producing the best rounds from the late starters.
Westwood is still chasing an elusive first major after twice finishing third in this tournament - in 2008 and 2011.
The 47-year-old got off to a flying start as he birdied the 11th and 12th, having started on the 10th tee, and rolled in another at 15 in response to his first bogey of the day.
The two-time major runner-up traded birdies and bogeys on his second nine but finished with a birdie at the par-five ninth to move into a share of fifth place.
"It is gettable if you play well and hit the fairways," said Westwood about the usually tough Mamaroneck venue.
"It becomes a beast of a golf course if you begin missing fairways and greens in the wrong places. It is not going to get any easier."
McIlroy & Pieters enjoy new dad bounce
McIlroy, whose wife Erica gave birth to daughter Poppy two weeks ago, is playing in his first major since becoming a father last month and said being a dad "makes the hard days a little easier to get over".
The world number four had no reason to feel disheartened as one of the morning starters, however, hitting the turn at three under par after beginning his round on the 10th tee.
The 31-year-old, chasing a fifth major title and first since 2014, opened the tournament with a birdie, added another at the 13th and completed an impressive opening nine holes with a third on the 18th.
He bogeyed the first, his 10th, but a superb par-saving putt on the second was followed by a birdie at the par-three third to move back within one stroke of leader Thomas.
The former world number one then drove the sixth green to set up a long-range eagle chance that would have handed him the lead - but three-putted and made par.
McIlroy spoke about the importance of a good start earlier this week and will be encouraged by the 67 that represents his lowest opening round in the US Open since 2011 at Congressional, where he went on to win by eight shots.
"First round of a major you're always anxious to play well and maybe I've overthought it at times," he said. "I just went out and took what was given to me a little more relaxed and played really nicely.
"I think at a US Open, if you can get off to a good start, you're not chasing as much. And when you chase on US Open golf courses, that's when you can start to make mistakes and compound your errors."
Pieters, whose best major finish is tied fourth at the 2017 Masters, has recently returned to competitive golf after becoming a father himself and also started well, opening with a four-under 66.
"It has, in a way, freed my mental game," he said about the birth of daughter Florence after his impressive first round.
"I have not been so perfectionist or angry, I don't get upset about anything anymore."
Thomas sets the pace on day one
Leader Thomas, playing alongside 15-time major champion Tiger Woods, bogeyed the tricky par-three third to wipe off an opening birdie, but another birdie at six followed by three in a row around the turn put him in pole position.
Thomas then held a lengthy discussion with a rules official over a bunker shot at 17 and, after being told not to alter his lie, found another bunker beside the green.
The 27-year-old splashed out superbly and tapped in for par to maintain his lead heading to the last, where he rolled in his sixth birdie of the day to move clear of Reed.
"It's one of the best rounds I've played in a while, tee to green," said world number three Thomas.
"There are a couple things here and there that definitely could have been better, but I made sure all of my misses were in the right spot, and that's what you have to do at a US Open."
American Xander Schauffele, one of the favourites going into the tournament, is three off the lead while world number two Jon Rahm's bid to become the first Spaniard to win the US Open began with a one-under 69.
Woods had rallied his way to one under par with three successive birdies through the turn and was walking after another birdie putt at 12 to make it four on the bounce, only to watch it lip out.
The 44-year-old's card was scarred by six bogeys though, and a double bogey at the last saw him finish three over par.
In-form world number one Dustin Johnson, who won the FedEx Cup, also struggled, signing for a 73 that leaves him eight shots off the pace.
Phil Mickelson, who infamously double-bogeyed the final hole at Winged Foot 14 years ago to blow an opportunity of winning the only major to elude him, hit just two of 14 fairways on his way to finishing nine over.
Justin Rose also found the West course hard to master as the Englishman, winner of this title in 2013, finished his opening round at three over par.
Countryman Matt Wallace closed with a birdie to head into the second round at level par, but Tyrrell Hatton, Tommy Fleetwood and Matthew Fitzpatrick all slipped to four over, and Ian Poulter, who tied for 12th here in 2006, is a shot further back.
Defending champion Gary Woodland opened with a 74, two shots better than playing partner, Ireland's Open champion Shane Lowry.
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