(Chris Keane/USGA)

Chen, 20, of Chinese Taipei, will try to avenge her 10-and-9 loss at the hands of Diaz-Yi, 18, of Thousand Oaks, Calif. Chen reached the Women’s Amateur quarterfinals with Thursday victories over Kacie Komoto and 2012 U.S. Girls’ Junior champion Minjee Lee, while Diaz-Yi eliminated stroke-play medalist Yumi Matsubara and Kendall Prince.

Diaz-Yi and Prince fought a seesaw battle for the first nine holes of their third-round match. Prince, 20, of Lake Oswego, Ore., twice took a 1-up lead, only to see Diaz-Yi come back each time to square the match. She sensed the chance for a fresh start on the inward nine.

RELATED CONTENT:Meet The Women's Amateur Quarterfinalists“When we made the turn, I felt like I had finally warmed up,” said Diaz-Yi, who reached the Round of 16 with a 2-and-1 win over Matsubara. “I feel like I always seem to turn it around on the back nine.”

Turn it around she did. After playing her first nine holes at three over par (with the usual match-play concessions), Diaz-Yi took the lead for good with the first of five consecutive pars at the par-4 10th. She capped a 4-and-3 victory with a birdie at the par-5 15th.

“It was pretty intense,” said Diaz-Yi, an incoming freshman at the University of Virginia. “(There were) a lot of crucial putts I missed here and there, and I gave up strokes like that on the front nine, but I was able to make them up on the back nine.”

Diaz-Yi knows that Chen, who only trailed for a total of two holes in her two Thursday matches, is not likely to repeat the poor showing she had during their WAPL match at Jimmie Austin OU Golf Club in Norman, Okla.

“Knowing Doris, she’s going to want revenge,” said Diaz-Yi, who is attempting to become only the third player to take the WAPL and Women’s Amateur title in the same year, joining Pearl Sinn (1988) and Jennifer Song (2009).

In the afternoon’s Battle of Long Island, reigning NCAA champion Annie Park, 18, of Levittown, N.Y., was 3 down through 10 holes against Kelly Shon, 21, of Port Washington, N.Y. But Park then went on a roll, winning holes 11-13 to erase Shon’s lead.

“On the back nine, I started to get my momentum,” said Park, who took stroke-play co-medalist honors at the 2013 WAPL (along with Chen), but fell in the first round to the 64th-seeded Ciera Min. “(I thought) I am just going to hit good shots and get out of there.”

Shon’s bogey at the par-4 17th handed Park her first 1-up lead of the match, and she held on tight for the 1-up victory. Park had earlier reached the third round by defeating Hawaiian Brittany Fan, 3 and 2.

Park will face Yueer Cindy Feng in Friday afternoon’s quarterfinals. Feng, 17, of Orlando, Fla., survived Thursday with a 4-and-2 morning victory Emily Collins, of Colleyville, Texas, and a hard-fought 1-up battle with 2013 U.S. Women’s Open low amateur Casie Cathrea, of Livermore, Calif.

“The afternoon was really a lot of back and forth,” said Feng of her match with Cathrea, which ended when the incoming Oklahoma State University freshman was unable to make par at the 18th hole. “Casie and I really didn’t play our best; we kind of left a few out there.”

Alison Lee, the 2012 U.S. Girls’ Junior runner-up from Valencia, Calif., needed 19 holes to eliminate local favorite Katelyn Dambaugh, of Goose Creek, S.C., in the morning’s second round. Her afternoon, however, was much easier. The 18-year-old incoming UCLA freshman built a 5-up lead through nine holes and coasted to a 3-and-2 victory over Alexandra Harkins, of Crystal Lake, Ill.

Lee’s Friday opponent will be Katelyn Sepmoree, 22, of Tyler, Texas. The former University of Texas player, who has limited match-play experience, eliminated Laura Wearn, of Charlotte, N.C., by a 2-and-1 margin in the morning round and notched a 1-up afternoon win over Aurora Kan, of Boothwyn, Pa.

“It’ll be a great match and I look forward to it,” said Sepmoree of her impending match with Lee. “She’s a great player and I enjoyed getting to play with her in a practice round, but I assume it’ll be just as much of a fight as I’ve been in. “

The fourth quarterfinal match will feature Emma Talley, of Princeton, Ky., and Australian Su-Hyun Oh. Talley’s morning 8-and-7 victory over Tatiana Wijaya was the largest margin of victory in a Women’s Amateur match since Cindy Lacrosse took a 9-and-7 victory over Pennapa Pulsawath at the 2008 championship at Eugene (Ore.) Country Club. Talley later notched a 2-up third-round win over Mexico’s Maria Fassi.

Oh, the second-ranked player in the Women’s World Amateur Golf Ranking, trailed for much of her second-round match with Grace Na, but eked out a 2-and-1 win. Her afternoon match with Cammie Gray was a different story, as Oh never trailed in the 5-and-4 victory.