Reigning champion Yuka Saso slumped to a 6-over 77 in the first round of the U.S. Women's Open on Thursday, while compatriot and last year's runner-up Nasa Hataoka shot an even-par 71.
Saso, who beat Hataoka in a three-hole playoff last year, had a day to forget after bogeying eight holes while sinking just two birdies at Pine Needles Lodge and Golf Club.
Saso claimed she "didn't feel the pressure" of being the reigning champion, but the 20-year-old had just a 35.7% success rate in hitting the fairways.
"The result wasn't good and that's the main issue," she said. "It's quite hard to fix your tee shots once you get onto the course. I need to adjust my play."
Hataoka also had a turbulent round but eventually finished the day in 28th place after carding five birdies, three bogeys and one double bogey.
"I'm aiming for a 2-under each day so it's really disappointing not to have done that," she said. "But it's big I managed to get myself back even with the birdie on my final hole."
Mina Harigae of the United States shot a 64 to take a one-stroke lead over Sweden's Ingrid Lindblad.
Mao Saigo, who has five wins on the domestic tour this season, and Sakura Koiwai placed highest among players from Japan, after both shot 70.
Yuna Nishimura and amateur Saki Baba both finished with 73, while Ayaka Furue, who came second at the Bank of Hope LPGA Match-Play on Sunday, fired a 74. The 2019 Women's British Open winner Hinako Shibuno had a 76.