Reigning U.S. Girls’ Junior champion Erica Shepherd, 17, of Greenwood, Ind., and partner Megan Furtney, 17, of Chicago, Ill., played the equivalent of 13-under-par golf in winning a pair of matches on Tuesday to advance to the semifinals.

On another unseasonably chilly Southern California day – temperatures hovered in the 50s with wind gusts as high as 14 mph – Shepherd and Furtney, both Duke University commitments for 2019, registered eight birdies in defeating Pepperdine University teammates Momoka Kobori, 19, of New Zealand, and Hira Naveed, 20, of Australia, 2 and 1, in the afternoon quarterfinals.

Earlier in the day, Shepherd and Furtney eliminated University of Arizona teammates Haley Moore, 19, of Escondido, Calif., and Gigi Stoll, 21, of Tigard, Ore., by the same 2-and-1 margin. With the usual concessions for match play, the two sides combined for 10 birdies and two eagles.

Meet the 2018 semifinalists

“Yeah, it was a hard-fought match,” said Shepherd of the quarterfinals victory. “We had some good birdies. We had three birdies in a row [on Nos.] 8, 9 and 10, and the chip-in on 9. I think that was really the turning point where we knew we had good control of the match.”

Shepherd and Furtney will face Colorado State University teammates Ellen Secor, 20, of Portland, Ore., and Katrina Prendergast, 20, of Sparks, Nev., in the first of the two semifinal matches on Wednesday, beginning at 7 a.m. PDT.

The other semifinal match at 7:15 a.m. pits Southern Californians and No. 2 seeds Leila Dizon, 18, of Los Angeles, and Irene Kim, 17, of La Palma against Yuchan Chang, 17, of Chinese Taipei, and Lei Ye, 16, of the People’s Republic of China, who opened stroke play on Saturday with a championship-record-tying 8-under-par 64.

Secor and Prendergast, who have qualified for next week’s NCAA Division I regionals in Austin, Texas, as individuals, were taken to the 18th hole for the first time in three matches in the quarterfinals by Kansas State graduates Katherine Gravel-Coursol, 24, of Canada, and Paige Nelson, 23, of Farmers Branch, Texas, before prevailing, 1 up. Secor holed a 15-foot birdie putt on the par-5 17th for what proved to be the difference, as the sides halved No. 18.

Ye and Chang, both students at the IMG Academy in Bradenton, Fla., broke open a tight quarterfinal match against future University of Oregon teammates Briana Chacon, 17, of Whittier, Calif., and Ty Akabane, 17, of Danville, Calif. The side made three birdies and a clutch par save on the inward nine in a 3-and-2 victory.

Ye, who has committed to attend Stanford University in 2019, stuck her approach on the par-4 11th hole to 10 feet to set up a birdie to go 1 up. She then made a 25-foot par save two holes later to maintain the side’s narrow lead. Ye had made a similar putt for birdie in the side’s 3-and-2 Round-of-16 victory earlier on Tuesday over Lauren Gomez and Olivia Yun.

Chang, headed to the University of Arizona this fall, closed out the match with 21-foot birdie putts on 15 and 16.

Dizon, a former Drive, Chip & Putt national finalist who is headed to the University of Pennsylvania this fall, and Kim, closed out their match against Chloe Schiavone, 16, of Jacksonville, Fla., and Izzy M. Pellot, 13, of Altamonte Springs, Fla., in dramatic fashion. Leading 1 up on No. 18, Kim, who has committed to attend Northwestern University in 2019, holed out from a greenside bunker to clinch the match.

Earlier in the match, Kim chipped in for birdie on No. 13 to give the side a 3-up lead. This ended a stretch of four consecutive birdies. Schiavone closed the gap with wins on Nos. 15 and 16, but after winning their first two matches in extra holes, they could not complete the comeback.