Golf-Choi carries on surge of youth at U.S. Women's Open

BETHLEHEM, Pennsylvania, July 9 (Reuters) - U.S. Women's Open leader Choi Na-yeon, continuing a well-established trend of young players making their mark at majors, exuded confidence on Thursday in her quest to make her first LPGA Tour win a major.

Choi shot a three-under-par 68 at the challenging Saucon Valley Old Course to lead world number one Lorena Ochoa of Mexico and 2007 champion Cristie Kerr by one stroke.

The 21-year-old Choi has made a great start to her LPGA career -- posting nine top-10 finishes last year in her rookie season -- but is without a victory.

Last year Yani Tseng of Taiwan, then 19, won the LPGA Championship for her first win, and South Korean Park In-bee claimed the U.S. Open for her first title, becoming its youngest winner at age 19.

Last month 22-year-old tour rookie Anna Nordqvist of Sweden won the LPGA Championship for her maiden victory.

Choi vowed not to be intimidated by the big stage.

"During my practice rounds I thought this was probably the most difficult course I've ever played in my career," the Seoul native told reporters through an interpreter.

"But starting today, I just wasn't very intimidated by this course. I know it's a difficult course, but I was really excited to start my round today, and I thought this was going to be a very, very interesting week for me."

Choi launched her week impressively. Beginning her round on the 10th hole she started with three birdies in a row, sticking two of her laser approach shots within two feet.

She also holed out from a bunker and sank a 60-foot birdie putt during her electrifying tour of the 6,740-yard layout.

The slender, 5' 5" (1.65 m) Choi has notched four top 10s this season, including a tie for eighth place at last month's LPGA Championship at Bulle Rock.

"We prepare the same way for every tournament on the tour, but it being a major tournament, definitely there's a little bit more dedication," said Choi.

"I just did my best to play smart golf today."

(Editing by Greg Stutchbury; to query or comment on this story email sportsfeedback@thomsonreuters.com)