The 14-year-old from Hermosa Beach, Calif., returned a flawless round of five birdies, four from tap-in distance, on the 6,312-yard Jack Nicklaus design. Lee sits one stroke ahead of Lilia Khatu Vu, who is at 4-under 68, and two ahead of Nicole Morales, Hannah O’Sullivan and Bethany Wu, who all carded 3-under 69s.

The 2013 U.S. Girls’ Junior Championship is open to female amateur golfers under the age of 18. It consists of 36 holes of stroke play followed by six rounds of match play, with the championship scheduled to conclude with a 36-hole final on Saturday.

The U.S. Girls’ Junior is one of 13 national championships conducted annually by the United States Golf Association, 10 of which are strictly for amateurs.

Lee came to Fort Wayne to compete in her first USGA championship. But while she may be new to the event, she is certainly familiar with the venue, as Sycamore Hills has served as host for the past three Junior PGA Championships.

“You need to think a lot (about the course). It's pretty tough,” said Lee, whose previous low round at Sycamore Hills was a 71 in 2012. “I just tried to play one shot at a time.”

Lee’s deliberate thinking certainly paid off. She opened with a bang, carding birdies on the opening three holes. A steady pace – and a lighthearted attitude – carried her through the remainder of the morning.

“I felt really comfortable,” said Lee. “I wasn't even thinking about the score. I was just having fun with my caddie.”

Today’s round was yet another highlight in Lee’s summer. Two weeks ago, she finished second at the Rolex Tournament of Champions, and just last week, her 4-0 record helped propel the West Team to victory at the Wyndham Cup.

“(Today gave me) a lot of confidence going into tomorrow and the rest of the week,” said Lee. “Playing like I did today is what I want to do.”

Like Lee, Vu went undefeated at last week’s Wyndham Cup. But unlike Lee, the 15-year-old from Fountain Valley, Calif., made the trip to Fort Wayne without previous experience at Sycamore Hills. Vu’s five birdies to only one bogey belied her lack of course knowledge.

“My first birdie got me started and I just tried hitting it close and parring it,” said Vu, who is competing in her third Girls’ Junior. “If not, maybe I'll get lucky and get a birdie.”

Reigning Girls’ Junior champion Minjee Lee began her title defense with a solid 1-under 71. Casie Cathrea, who earned low-amateur honors at last month’s U.S. Women’s Open, carded an even-par 72, while 2012 Girls’ Junior quarterfinalist Kelli Murphy struggled to an 8-over 80.

Seventy-eight players remain on the course for the afternoon wave, including 2013 U.S. Women’s Open competitors Yueer Feng and Gabriella Then.

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