Japan's Ayako Uehara fired a seven-under par 65 to seize a one-stroke lead after Thursday's opening round of the LPGA Portland Classic.
The 38-year-old veteran, chasing her first LPGA title, birdied three of the last four holes to top the leaderboard at Columbia Edgewater Country Club in Portland, Oregon.
Uehara, whose most recent of three career triumphs in Japan came in 2011, is only just back this month after a lung issue sidelined her for more than a year.
"This is my third tournament," Uehara said. "I'm very excited about it and then glad to be out here. I'm looking forward to tomorrow again."
Australia's Hannah Green, the 2019 Portland champion, was second on 66, with Japan's Ayaka Furue and Hinako Shibuno and Americans Nelly Korda and Caroline Inglis on 67.
Uehara saved par on the first two holes after missing the green.
"One and two I did good up and down and that's so much help," she said. "I think today's key is just number one and then number two."
She birdied the third, and then reeled off three birdies in a row starting at the par-5 fifth hole and added another at the ninth.
After her lone bogey at the par-3 13th, Uehara answered with a birdie at the 15th and closed with back-to-back birdies to seize the lead, which she vowed won't change how she plays.
"I'll do just my game and then focus one at a time," she said.
Green, who captured a major title at the 2019 Women's PGA Championship, took a bogey at the par-3 third but answered with birdies on seven of the next 10 holes.
"I made a bogey at the third when I missed a four-foot putt, but then I made a 20-footer on the next hole," Green said.
"Just seeing them go in gives you big confidence and knowing what I've achieved here, it was a great start."
She added a birdie at the par-3 16th, but a closing bogey cost her a share of the lead. Still, her history at Portland bolstered her throughout the round.
"It's a big factor to why I played well," Green said. "Really pleased with six-under."
Sharing seventh on 68 were Canada's Brooke Henderson and Alena Sharp, South Korean Jenny Shin, American Lilia Vu, Dutchwoman Anne van Dam and Hong Kong's Tiffany Chan.