KOHLER, Wis. — Americans Cristie Kerr, Brittany Lincicome and Lizette Salas shot 3-under 69 on Thursday to share the first-round lead in the U.S. Women's Open.

Ai Miyazato, coming off a victory Sunday in the LPGA Tour event in Arkansas, was a stroke back along with 17-year-old Lexi Thompson, Jennie Lee and Beatriz Recari.

Defending champion So Yeon Ryu opened with a 74 as players struggled in the nearly 100-degree heat and high humidity at Blackwolf Run.

Se Ri Pak, the 1998 Open winner on the course, had a 72.

Top-ranked Yani Tseng shot a 74. She would become the youngest player to complete a career Grand Slam with a victory this weekend.

Second-ranked Stacy Lewis opened with a 77.

Kerr has 14 career LPGA wins and was the 2007 U.S. Women's Open champion.

Conway native Kristy McPherson shot a 3-over-par 75 in the first round and is tied for 55th.

She teed off on the 10th hole and got off to a strong start, with a birdie on her first and sixth holes sandwiching a bogey on her fourth hole. She was tied for third in the morning wave through 12 holes, but struggled down the stretch with a bogey on her 13th hole, double bogey on her 14th and bogey on her 17th.

European Tour

Christian Nilsson of Sweden shot a 6-under 65 to lead by a stroke after the first round of the French Open.

Nilsson made seven birdies and only one bogey on Le National.

The 263rd-ranked Nilsson has not finished in the top 30 this year. He won his only title on the European Tour at the Saint-Omer Open in 2009.

Gary Boyd of England and Matteo Manassero of Italy shot bogey-free 66s to share second place with Wales Open winner Thongchai Jaidee of Thailand.

David Lynn of England, Federico Colombo of Italy and Gonzalo Fernandez-Castano of Spain were in a tie for fifth place, two strokes off the lead.

Many favorites struggled on a tough golf course where 11 holes are surrounded by water. Lee Westwood recovered from a poor start to shoot a 70.

The former top-ranked Englishman dropped four shots in his first six holes, but finished with five birdies.

“I feel like I’ve got a couple of snails on my feet,” Westwood said after standing in the lake to save par on his last hole.

Westwood found the water on the ninth and rolled up his trousers to steer the ball clear of the lake.

“After Thomas Levet jumping in there and breaking his leg last year, I wasn’t sure what was in there,” Westwood said. “So I kept my shoes on. I was on the last hole and I had brought plenty of shoes on me … I was more worried about the trousers than the shoes really.”

Defending champion Levet shot a 72. British Open champion Darren Clarke (70) and European Tour leader Justin Rose (71) also stayed in contention.

The 2010 U.S. Open champion Graeme McDowell (72) and 2009 winner Martin Kaymer of Germany (73) are in danger of missing the cut.