ORLANDO, Fla. (AP) -- Na Yeon Choi shot a 6-under 66 on Thursday to take a one-stroke lead over Morgan Pressel and Karrie Webb after the first round of the LPGA Tour's season-ending Titleholders.
Choi, the LPGA Malaysia winner last month, birdied five of the first eight holes on the back nine at Grand Cypress before dropping a stroke with a bogey on the par-4 18th.
"I think from after the British Open, I had a great feeling about my game," Choi said. "After that, I played like consistently, I think, and then especially at Mizuno I had a great final round. I shot 8-under par. And then I think I took something from Mizuno to here."
Defending champion Maria Hjorth and Cristie Kerr shot 68, and Anna Nordqvist was another stroke back along with Paula Creamer, Sandra Gal, Mi Hyun Kim, Candie Kung, Azahara Munoz and Dewi Claire Schreefel.
Top-ranked Yani Tseng had a 70, and Michelle Wie opened with a 71.
Pressel is winless on the tour since the 2008 Kapalua LPGA Classic.
"I think I just need to become comfortable again being around the top of the leaderboard and giving myself chances week in and week out," Pressel said. "That's why I play. That's what I'm here to do. I come to a tournament, and my first goal is to win.
"I felt good out there today. I didn't feel like I was pressing too hard. I know that it's I have a bad habit that I've gotten into and that's when things start to go well then I start to press and almost become afraid of the hole. So I was able to stay patient, stay with my game throughout the entire round, so hopefully I can continue to do that for three days."
Choi and Pressel were paired together. They combined for 10 back-nine birdies.
"I had five birdies on the back nine, and then I think Morgan, she played well, too, and then when she hit close to the pin or when she made a birdie putt, I think something motivated me," Choi said. "I had fun playing with Morgan and Sun Young. ... I think everything clicked on the back nine."
Choi has replaced her 5-iron with a hybrid.
"I hit like five or six times with that new club, and then I made four birdies with that club," Choi said. "I like that new club."
Webb has struggled after winning the HSBC Women's Champions in Singapore in February and the LPGA Founders Cup in Phoenix in March in consecutive starts.
"I obviously got off to a great start and with that I think expectations rose a little bit," Webb said. "I had a good U.S. Open, one of my better ones for a while, so I was happy about that but then a disappointing Evian and the British, and really a flat time with that."
Webb has made swing changes with coach Ian Triggs.
"Ian tried not to do too much through the majors, but really at the end of the day, that didn't happen because I didn't play as great as I would have liked through that stretch," Webb said. "So when we were in Korea we decided it didn't matter how I played through the rest of the year, that I needed to get going on that. It was almost overwhelming because I got a lot of information in a one week span, so it took a while for it to all sort out in my head."
Kerr is winless this season after winning in each of the last seven years.
"It's felt like a bit of bad luck," Kerr said. "It's felt like you know, some of the tournaments where I came in second I played awesome but somebody played better. That's the way it goes sometimes."