Starting on the 10th hole, Yin’s first nine holes included three birdies and two bogeys. She then lit on fire on her second nine, converting five birdies and closing in 5-under 31.
With the day’s tees moved up and the par-72 Meadow Course playing to 6,526 yards, the long-hitting Yin took full advantage. The thin mountain air also played to her advantage, with the Arcadia High rising junior belting some of her drives 300 yards.
“The par 5s, I could reach them because they’re shorter,” said Yin, who made the cut at this year’s Kraft Nabisco Championship on an amateur exemption. “It was pretty short for me.”
Arizona seems to bring out the best in Yin. This is the third time she has returned a 66, her lowest competitive round, in an Arizona-based event. She shot a 66 in the second round of the 2012 Joanne Winter Arizona Silver Belle Championship, held at Whirlwind Golf Club in Chandler, as well as in the first round of the 2012 Winn Grips Heather Farr Classic, held at Longbow Golf Club in Mesa.
Megan Khang, 16, of Rockland, Mass., and Jennifer Kupcho, 17, of Westminster, Colo., share second at 3-under 69. Khang, who last month played in her second U.S. Women’s Open, is competing in her sixth U.S. Girls’ Junior, one shy of the record set by Margot Morton (seven championships from 1954-60).
Four players are tied for fourth at 2-under 70, led by three-time Mexican Amateur champion Marijosse Navarro, 17, of Mexico. She is joined by Virginia Green, 15, of Point Clear, Ala.; Mary Janiga, 17, of Wellington, Fla.; and Princess Mary Superall, 17, of the Philippines.
Local favorite Hannah O’Sullivan, 16, of Paradise Valley, Ariz., opened with a 1-under 71 and is tied for eighth.
Andrea Lee, who made the cut at the 2014 Women’s Open, carded a 2-over 74.
Seventy-eight players had afternoon tee times, including 2014 U.S. Women’s Amateur Public Links runner-up Eun Jeong Seong, 2013 Girls’ Junior medalist Bailey Tardy and 2014 Women’s Open competitor Kathleen Scavo.
Christina Lance is the assistant manager of communications for the USGA. Email her at email@example.com.