Gillman, who recently won the Junior Girls PGA Championship by 11 shots, was four-down to Oh through 12 holes before the Austin, Tex. native won four of the final six holes to send the quarterfinal match to extra holes.

After Oh and Gillman made three on the par-three 10th hole, Gillman sank a birdie putt to complete the comeback on 11, sending her into the semifinals.

Because of her Junior Girls PGA win, the 2016 University of Alabama commit will get to play in next year's LPGA Tour Swinging Skirts event at Lake Merced Golf Club in Daly City, Calif.

15-year-old Andrea Lee of Hermosa Beach, Calif. is advancing to the semifinals to face Gillman. The 2016 Stanford University commit defeated 14-year-old Eunjeong Seong of South Korea 2-and-1. Lee won four of the first five holes with Seong fighting back on holes eight and nine to bring the match back to within two. Lee and Seong pushed every hole on the back nine, however, as a par by Lee on the par-four 17th sealed the victory.

16-year-old Hannah O'Sullivan of Paradise Valley, Ariz. owned the largest margin of victory on Friday as she handed former Pepperdine University All-American Grace Na a 5-and-4 beating. The match was all-square through five holes before O'Sullivan won five of the next eight holes, closing out the match with a par on 14.

O'Sullivan has an impressive resume as a junior, qualifying for the 2012 U.S. Women’s Open at age 14 and winning the 2010 California Junior Girls’ State Amateur at age 12, which made her the event’s youngest winner.

She will face Canadian Brooke Mackenzie Henderson, another 16-year-old, in the semifinals, who won a tight one-up quarterfinal match over UCLA's Allison Lee.