Cristie Kerr shot a tournament-record 8-under 64 on Thursday to take a three-stroke lead over Stacy Lewis in the Lorena Ochoa Invitational, while Ochoa opened with a 74 on her home course in her first LPGA Tour start since retiring in April.
Michelle Wie, the winner last year for her first LPGA Tour title, withdrew after the round because of a back injury. She shot a 78.
''I was very excited to be here, but unfortunately I can't play anymore,'' Wie said. ''I'm going to see the doctor tomorrow and hope to make it feel better. We took an MRI and I have two little cysts near my spine and a little disc bulge. It's nothing major but it's just something I can't play with.''
The third-ranked Kerr birdied nine of the first 15 holes at Guadalajara Country Club, but dropped a stroke on the par-3 17th. She won the LPGA State Farm Classic and LPGA Championship in consecutive starts in June.
''I felt really good out there,'' Kerr said. ''I was there every shot. I want to do the small things well and take it day by day. I won today for myself, and I'll go out there tomorrow with the same amount of confidence.
''When you're swinging well, you have good confidence and a I had lot of good yardages into the hole today,'' Kerr said. ''So, I had good control of my ball, and if I have good control of my ball, then I can still be aggressive. Every day's different.''
Japanese star Ai Miyazato, U.S. Women's Open champion Paula Creamer, South Korea's Na Yeon Choi and Australia's Katherine Hull shot 68s, and South Koreans Hee Young Park and In-Kyung Kim had 69s.
Ochoa closed with her second double bogey of the round.
''It's good to be back,'' Ochoa said. ''It would be better if I had a better round today. Especially the end of the day was a tough one because I tried really hard to stay around par and just finish really good. But nothing I can do now.''
Her husband, Aeromexico CEO Andres Conesa, caddied for her.
''He did pretty good,'' Ochoa said. ''I was very impressed. But I know talking to him he did a good job. He was taking care of his duties.''
The course sits more than a mile above sea level, making club selection difficult in the thin air
''It's actually really hard,'' Lewis said. ''I'm still kind of adjusting. I think it's somewhere between 5 and 10 percent, depending on how long the shot is and how long it's in the air and things like that. But I had some shots today that just went crazy far for me. So I'm still trying to adjust.''
Yani Tseng, 14 points ahead of second-place Miyazato in the player of the year race, struggled to a 76. Top-ranked Jiyai Shin, skipping the tournament, and Choi are tied for third, 18 points behind Tseng. Kerr is fifth, 22 points behind Tseng.
''This tournament is definitely key. We have 35, 36 of the best players in the world here, and everybody's playing well,'' Kerr said. ''So for me to try and accomplish the goals that I have of player of the year and so on, I have to keep doing what I did today.''
