Ochoa is coming off her second straight major title, a one-sided win at the Kraft Nabisco Championship. She is seeking her fourth victory of the year.
She recorded two eagles to fire a 7-under 66 at the Tres Marias Golf Club and was tied for the lead with Song-Hee Kim. Ochoa has won 17 tournaments in the last 24 months and could qualify for a spot in the LPGA and World Golf Halls of Fame if she wins this week.
"I managed to have that (the Hall of Fame) out of my mind and stayed relaxed," Ochoa said. "The conditions were good and I'm glad I took advantage of that."