Cristie Kerr, Brittany Lincicome and Lizette Salas each posted rounds of 3-under 69 on Thursday to share the opening-round lead of the U.S. Women's Open.

Kerr, the 2007 U.S. Women's Open winner, Lincicome, the 2009 Kraft Nabisco Champion, and Salas braved the elements better than anyone Thursday at Blackwolf Run.

Temperatures reached the high 90s on Thursday with the heat index exceeding 100 degrees. Combine that will very long rounds, and it was a demanding opening day.

"It was a bad combination," said Lincicome. "I felt like we were out there waiting on every single hole. You kind of have to take your mind on somewhere else and not focus on obviously what you're doing."

Last week's winner in Arkansas, Ai Miyazato, 17-year-old Lexi Thompson, Beatriz Recari and Jennie Lee are knotted in fourth place at 2-under 70.

World No. 1 Yani Tseng, who needs this title to complete the career Grand Slam, Michelle Wie, LPGA Champion Shanshan Feng, and defending champion So Yeon Ryu, are part of a group at 2-over 74.

"I played my best today. I only had two bad holes," said Tseng, who recorded a triple bogey and a double bogey in Thursday's first round.

Everyone is chasing the American trio on top.

Kerr, who is winless since her major victory at the 2010 LPGA Championship, was flawless on Thursday. She kicked off her round on the 10th tee and birdied 11, 13 and 16 to vault into the lead at 3-under par.

She stayed on that number through her second nine thanks to all pars on her second side.

"I played really well. It could have been lower," acknowledged Kerr. "I hit four good putts that didn't go in, but that's the U.S. Open. You never know when the light switch turns on, and I feel like it has."

Lincicome started on the 10th tee Thursday and birdied her first hole from five feet out. At the par-3 17th, Lincicome nearly holed an 8-iron, but settled for a tap-in birdie.

After the turn, Lincicome three-putted from just off the first green for a bogey. She got the stroke back with a 15-foot birdie putt at the par-5 second.

Lincicome was in the fairway at the fifth, but pulled her 9-iron approach from a side-hill lie into the water. She was able to manage a bogey, but that was the last blip on the round for Lincicome.

She birdied No. 6 and came up just short of the green with her second at the par-5 seventh. Lincicome chipped to 12 feet, holed the putt, then parred out for her share of the lead.

"I was very pleased. Coming into this week and playing the practice rounds, you're out there and you're like, oh, my gosh, 5-, 6-, 7-over is going to win this event," said Lincicome. "Obviously, today, shooting 3-under, I have to kind of rethink my strategy, and obviously under par is very doable."

Salas broke into red figures early thanks to a beautiful 9-iron approach to seven feet at the first. She converted the birdie effort and made her next birdie from about the same distance at the par-5 seventh.

Salas' only hiccup of the round came at 11. She drove into the right rough and "tried to be a little cute with it." Her approach went over the green and Salas couldn't save par.

Salas fell to 1-under par, but got back to minus-2 thanks to a 40-foot bomb at the 15th. She became the first player to get to 3-under after she hit a 6-iron to seven feet at the last.

"We just figured any putt on the green is a birdie putt," said Salas, whose parents emigrated from Mexico when she was young. "And we had some good up- and-downs, and down the stretch we had some good birdie opportunities, and took advantage of that last one, and just threw out a fist pump. It was good."

Salas, 22, received a congratulatory text from her hero, Nancy Lopez, after her round on Thursday.

"I don't know how she got my number, but she called me right before my debut on the Futures Tour on the Duramed Tour last year," said Salas, who tied for 15th at last year's U.S. Women's Open and won her qualifier this year in Phoenix. "Just so happened she texted me not too long ago asking me to call her."

Inbee Park, the 2008 winner, Suzann Pettersen, Na Yeon Choi, Meena Lee, Sandra Gal, Mika Miyazato and Vicky Hurst are knotted in eighth place at 1-under 71.

NOTES: Se Ri Pak, who won the 1998 U.S. Women's Open the last time it was at Blackwolf Run, shot an even-par 72...Cheyenne Woods, the niece of Tiger Woods, had a 3-over 75...Kraft Nabisco winner Sun Young Yoo shot a 76, and world No. 2 Stacy Lewis was one worse with a 77.