'My game has improved so much,' said Cochran, who is appearing in her first Women's Amateur. 'I make so many more up-and-downs and I hit it a little farther. My iron game has improved too.'
Julieta Granada, the 2004 U.S. Girls' Amateur winner, shot the round of the day with a 2-under 70. She climbed into a share of second place at 1-under-par 143, where she is joined by Sun-Young Yoo (71) and Hee-Young Park (71). Nicole Cutler stands alone in fifth place at 1-over-par 145.
Morgan Pressel, who won the prestigious North and South Women's Amateur at Pinehurst earlier this summer, is joined in sixth place at 2-over by Karen Dennison and last year's runner-up, Jane Park.
In-Bee Park, the 2002 U.S. Girls' Junior amateur champion, advanced to the match play portion at 3-over-par 147, where she was joined by Diana Ramage.
Among the other prominent players to move on to the first round of match play were Kristen White (plus-5), Brittany Lincicome (plus-6), Angela Park (plus-7), Paula Creamer (plus-8), Elizabeth Janangelo and Michelle Wie (plus-9) and Isabelle Lendl (plus-10).
The cut line fell at 12-over-par 156, where 11 players finished and will play off for the final spot on Wednesday morning at 7:30 a.m. (et). Those players are Meghan Bolger, Anna Temple, Kasi Lee, Erin Andrews, Sin Ham, Laura Terebey, Laura Crawford, Lisa Ferrero, Seema Sadekar, Hsiao-Ching Lu and Becky Berzonski.
The winner of the playoff will advance to face Cochran, who actually shot a 69 on Monday, but wrote down the wrong score on the sixth hole. She posted a birdie on the hole, but wrote down par on her scorecard. She did not receive a penalty for recording a higher score, but the score stands once the card is officially signed.
Among those missing the cut for the match play portion were 2003 Girls' Junior amateur winner Sukjin Lee Wuesthoff (plus-13), seven-time USGA champion Carol Semple Thompson (plus-13), Brittany Lang (plus-16), who was a member of the United States 2004 Curtis Cup team, 70-year-old Marlene Streit (plus-22), who is a four-time USGA champion, and Leigh Anne Hardin (plus-23).