The Arizona State sophomore followed her spectacular opening round with a solid 2-under 68 on Friday and at 9-under 131, will sleep on a one-shot lead over Antonia Malate of San Jose State, who carded a second-round 65 to move into sole possession of second place at 8-under 132.
Summerhays had four birdies against two birdies on her Friday card to maintain a slim lead over Malate, whose eight birdies more than offset three bogeys.
"It was a pretty even keel round," said Summerhays. "I hit some good shots when I needed to and made some putts and kind of got it going there at the end."
Heading into Saturday's final round, she feels to need to change the game plan that has worked so well for her the first two days at the Wigwam Golf Club outside of Phoenix.
"I've had a couple of experiences like this and I think the best plan for me is to stay aggressive. I don't think protecting anything is a good strategy so I'm just going to stay aggressive."
The low round of the day belonged to Oregon standout Brittany Shin, who turned a bogey-free 6-under 64 on the Blue Course to move into a tie for sixth at 4-under 136.
