Sydnee Michaels and Mika Miyazato shot 7-under 65 on Friday in 100-degree heat to share the first-round lead in the LPGA Tour's Safeway Classic.
Miyazato and Michaels each had eight birdies and a bogey on Pumpkin Ridge's Ghost Creek Course.
Michaels, the former UCLA player who won twice last year on the developmental Symetra Tour, had her best round of her rookie season. She's coming off a career-best 21st-place tie last week in the Toledo Classic.
"It's been hit or miss," Michaels said. "I'll be in contention and I might have a little shaky Sunday, and wind up top 30 or something like that or I'll miss the cut by one or two. I definitely feel that every week I learn something, and I'm hoping I'll start to hit my stride here toward the end of the season. Last year, I hit my stride at the end of the season, so I'm kind of hoping I follow that pattern."
Cristie Kerr, Inbee Park and Pornanong Phatlum were a stroke back. So Yeon Ryu, the Toledo Classic winner last week, was two shots behind at 67 along with Brittany Lincicome, Alison Walshe and Jee Young Lee.
Michelle Wie opened with a 69, top-ranked Yani Tseng had a 70, defending champion Suzann Pettersen shot 71, and second-ranked Stacy Lewis had a 73.
Wie has missed seven of 10 cuts this season, also struggled in two events without cuts and lost in the first round of the match-play event. She broke par for only the fifth time in 34 rounds this season.
"It's just one week it seems so easy and another week, or another year, for me everything seems so difficult," Wie said. "But I've got to stay positive. Nothing good will come out of it if you keep beating yourself up. The game is hard enough as it is without me doing that to myself.
"I'm just trying to stay positive after every round, looking at the positives and feeling good about each week and really trying not to doubt my game, because I know I have it."
Playing in the first group of the day, Michaels took advantage of cooler temperatures by making birdies on the first four holes. Playing the back nine first, she shot a 5-under 30, then finished with birdies on two of her final three holes. The early four-hole birdie spree ended with a chip-in at the 386-yard 13th.
"From there out it was OK, we got it going," Michaels said.
Michaels said she isn't a scoreboard watcher, but sensed her name was somewhere near the top.
"You can pretty much put two and two together when all those photographers are following you," Michaels said.
Michaels is the youngest of eight children, most of who were on hand to watch her play Friday.
"No one in my family plays, not even my parents. I don't think they even know what's going on. They clap when everyone else is clapping," Michaels said.
Miyazato, winless on the LPGA Tour, made four consecutive birdies during the middle of her round and pulled into a tie for the lead with a birdie on the 431-yard, par-4 18th, the toughest hole Friday.
The Japanese player has five top-10 finishes this season.
"My golf game is very confident right now," Miyazato said. "To begin the season, I was not so very good with my golf game. I start to shoot right in the last couple four, five events. I'm gaining more confidence."
Park had a chance to join the leaders after reaching 6 under through 15 holes with two par 5s remaining, but settled for a 66. Phatlum had a roller-coaster round, with nine birdies and three bogeys, and Kerr, who recently returned from a two-week vacation in Italy, birdied four of her final six holes.
"Probably the best opening round I've had all year," Kerr said. "I came back from Italy, and feel fresh." Mariajo Uribe had a hole-in-one on the 169-yard third hole. She shot a 71.