Matsubara won the first hole of the match and remained 1-up until the fourth hole, when Diaz-Yi squared the match with a par. It remained all square until Diaz-Yi made a birdie on the ninth hole, which she pinpointed as the turning point of the match.

“I think my putter was a little slow on the front, but once I made that putt (on No. 9) I felt a lot more confident,” said Diaz-Yi, who traded wins on the 15th and 16th holes with Matsubara, then closed out the match by winning No. 17. In the third round of match play Diaz-Yi faces Kendall Prince, 20, of Lake Oswego, Ore., who defeated Lori Beth Adams, 21, of Burlington, N.C., 2-up.

Two U.S. Girls’ Junior champions will play each other in the Round of 16 – 2010 champion Doris Chen, 20, of Chinese Taipei, and 2012 champion Minjee Lee, 17, of Australia.

Chen defeated Kacie Komoto, 18, of Honolulu, 3 and 2. The match was all square until Komoto bogeyed the sixth through eighth holes, while Chen made three pars to grab a 3-up lead. She maintained the advantage until the 13th hole when Komoto birdied, but Chen responded with a birdie on the 14th and eventually won the match on the 16th hole.

Lee eliminated Kotone Hori, 17, of Japan, 4 and 3. Lee, won the first two holes and then extended her lead to 4 up with back-to-back birdies on the seventh and eighth holes. Hori recorded a birdie at the 12th hole, but Lee answered with a birdie on the 14th and ended her bogey-free match on the 15th hole.

Another notable third round match-up pits a duo from Long Island: Annie Park, 18, of Levittown, N.Y., and Kelly Shon, 21, of Port Washington, N.Y. Park enrolled at the University of Southern California for this year’s spring semester and won the NCAA Division I Individual championship, becoming just the seventh freshman in history to do so. Shon plays for Princeton University and was named the 2012-13 Ivy League Player of the Year.

In the second round, Park defeated Brittany Fan, 17, of Honolulu, 2 and 1, and never lost the lead that she established on the first hole. Shon also won her first hole and maintained her early lead against Meghan Stasi, 35, of Oakland Park, Fla., a four-time U.S. Mid-Amateur champion and the only mid-amateur remaining in the field. Shon won, 3 and 1.

Emma Talley, 19, of Princeton, Ky., had the largest margin of victory in the Round of 32, defeating Tatiana Wijaya, 17, of Indonesia, 8 and 7. Talley recorded a bogey-free round that included two birdies through 11 holes. Wijaya described Talley’s game as perfect, saying, “Emma just doesn’t make mistakes.”

Talley will face Maria Fassi, 15, of Mexico in the third round of match play. Fassi eliminated Ally McDonald, 20, of Fulton, Miss., in 19 holes after trailing nearly the entire match. McDonald was 3 up with four holes to play, but Fassi won three of those holes, two with birdies, to send the match to extra holes. McDonald bogeyed the first hole while Fassi made par to advance to the Round of 16.

The 2012 U.S. Girls’ Junior runner-up Alison Lee, 18, of Valencia, Calif., defeated local favorite Katelyn Dambaugh, 18, of Goose Creek, S.C., in 19 holes. The match was all square through four holes until Dambaugh bogeyed the fifth hole, and two holes later Lee birdied to move to 2 up. Dambaugh birdied the ninth to cut the margin to 1 up, and squared the match when Lee bogeyed No. 12. However, Lee birdied the following hole to regainher 1-up advantage.

“I get a little fired up and that’s when I play better,” said Lee about her bogey-birdie swing. “So after that bogey, on my second shot (on No. 13), I said I’ve got to go for this. I just played it to my advantage.”

Lee fell back to all square again when she bogeyed the 16th hole, and the players halved the remaining two holes to advance to extra holes. With a sizable gallery following the match, Dambaugh bogeyed and Lee birdied to clinch her victory.

Cammie Gray, 20, of Northport, Ala., ousted the 2010 U.S. Women’s Amateur Public Links champion and 2012 Curtis Cup team member, Emily Tubert, 21, of Burbank, Calif., in 19 holes. Tubert won the first hole, but Gray won the second, and the match was all square until the fourth hole when Gray bogeyed to hand Tubert a 1-up lead.

Tubert kept that lead until making a bogey on the 11th hole, and then quickly regained it when Gray bogeyed the 12th. However, she bogeyed 18 while Gray made par to square the match and force extra holes.

On the 19th hole, Gray again made a par and Tubert bogeyed, advancing Gray into the third round of match play. Gray plays Su-Hyun Oh, 17, of Australia, who defeated Grace Na, 20, of Oakland, Calif., 2 and 1, in the second round.