SOUTHAMPTON, New York (AP) ― South Korea’s Kim Ha-neul upstaged friend Park In-bee to take the first-round lead at her first U.S. Women’s Open.

Kim shot a bogey-free 6-under 66 on Thursday at Sebonack to lead Park by a stroke. The top-ranked Park is trying to make history by winning the first three majors of the year.

“I’m enjoying myself,” Kim said through a translator. “I’m just happy to be here and to be playing in this big event. I’m not really thinking about winning or results but enjoying the moment.”

Currently a member of the KLPGA Tour, Kim is a seven-time winner in South Korea. She kept giving herself short birdie putts Thursday and making them.

Kim birdied her second-to-last hole with daylight waning to claim the lead after Park held it for most of the day with her 67 in the morning session.

No player has won the first three majors in a season with at least four majors. The 2008 U.S. Women’s Open champion, Park has already won five times this year, including her last two tournaments.

American Lizette Salas, Swedes Caroline Hedwall and Anna Nordqvist and South Korea’s Kim In-kyung shot 68.

Concerned about bad weather, tournament officials moved up the tees, and with the rain holding off, Park was able to play aggressively.

“I never had practiced from those tees, so I was a little bit shocked when I went to the tees,” Park said.

Not that she was complaining.

She repeatedly set up short putts, and the way she has excelled in her short game lately, Park was headed to a low score.

“So instead of hitting like 5-irons, we were hitting 9-irons, and that was making the course much easier,” she said. “I was actually able to go for some pins and give myself a lot of opportunities today. I made a lot of putts and didn’t leave much out there.”

Starting on No. 10, Park birdied her first hole, then started racking up pars. She made the turn at 2 under before birdies on three of her next four holes.

At 5 under, Park briefly struggled with her tee shots, needing to save par on Nos. 5 and 7. On No. 6, her 15th hole of the day, she had to lay up out of the tall grass and settled for her lone bogey.

Park got back to 5 under on the par-5 eighth with a chip shot to about 5 feet that set up a birdie putt.

Nordqvist birdied her last two holes to pull into a tie for third. Hedwall and Kim were each at 5 under with a hole left, but closed with bogeys.

Salas, a 23-year-old former Southern California star, played with Park in the last group of the final round of this year’s Kraft Nabisco Championship. Three strokes back starting the day, she opened with a double bogey and tumbled to 25th after shooting a 79.

She bounced back to reach a playoff at the LPGA Lotte Championship in April, losing to Suzann Pettersen for her best finish on tour.

AT&T National

BETHESDA, Maryland (AP) ― Roberto Castro missed the U.S. Open at Merion. It felt as if he was playing one Thursday in the AT&T National at Congressional.

The course that has hosted three U.S. Opens looked as though it could hold another in a moment’s notice. Only a dozen players shot in the 60s, with Castro leading the way at a 5-under 66 that required some of his best golf. He made three straight birdies late in his round with a 20-foot putt, a perfect 3-wood into a par 5 and a chip-in.

“It’s very similar in that there’s not a lot of birdies out there,” Castro said. “There’s not many good breaks or bad breaks to be had out there. If you drive it in the rough, you drove it in the rough. If you hit it in the fairway, you can go from there.”

The average score was just over 73, despite cloud cover for most of the day leading to soft conditions and only a light wind.

Billy Horschel, who tied for fourth in the real U.S. Open two weeks ago, began his day with a 50-foot birdie putt, added a pair of birdies over the next three holes and then hung on for a 68. That was the best score among the early starters. Bud Cauley and Graham DeLaet each had a 68 in the afternoon.

“It’s like another U.S. Open,” Horschel said. “Off the fairways, the rough is thick. Fortunately, the greens are soft so they’re really receptive. It’s still a tough golf course.”

The eight players at 69 included Jim Furyk, 19-year-old Jordan Spieth and Brandt Snedeker, whose round included a birdie on the par-5 ninth hole in which he covered more than the 635 yards it was playing.

Snedeker snap-hooked his drive into the rough and was blocked by trees, leaving him no choice but to chip backward or play down the adjacent fourth hole. He hit hybrid down the fourth, and just his luck, wound up on the member’s tee. From about 180 yards, he hammered a 6-iron through more trees, and the big roar told him he had reached the green. From there, he made a 55-foot birdie putt. Simple as that.

Irish Open

MAYNOOTH, Ireland (AP) ― Saying he’s “feeling a bit lost” in a difficult year, Rory McIlroy shot a 2-over 74 on Thursday in the Irish Open to fall eight strokes behind first-round leader Oscar Floren.

The second-ranked McIlroy, from Northern Ireland, had four bogeys and two birdies in wet and overcast conditions at Carton House on the outskirts of Dublin. McIlroy hit only five of 14 fairways and took 34 putts.

“At the moment, no aspects of my game are strong and I’m just feeling a bit lost at the moment,” he said. “It feels good on the range and I can hit all the shots, but when I get out on the course it really does not seem to be there.

“Off the tee, I am missing one right and then missing one left and it’s just not going where I want it. It gets you in two minds every time you are playing a tee shot. The game is just not coming easy to me at the moment and while I was struggling at this point last year, I was able to turn the corner in the middle of the summer and have a great end to my season. I don’t know whether it’s a matter of trying to play my way out of it or just keep grinding away on the range or whatever.”

Floren, from Sweden, had a 6-under 66. He drove the green on the par-4 13th and holed a 20-foot eagle putt.

Senior Players Championship

PITTSBURGH (AP) ― John Huston shot a 5-under 65 to take the first-round lead in the Senior Players Championship, the third of the Champions Tour’s five majors.

Huston started on No. 10 and was even par halfway through his round before making a big move on the front nine at soggy Fox Chapel. Huston shot 5-under 30 coming in, including four birdies and an eagle on the short par-4 seventh. The 52-year-old Huston missed three months this season because of lower back problems.

Fred Couples, Duffy Waldorf, Fred Funk and Russ Cochran were a stroke back. Colin Montgomerie had a 69 in his Champions Tour debut. The start of play was delayed nearly five hours because of heavy rain.