World number one Yani Tseng of Taiwan played a seven-hole stretch in seven-under on Thursday, her seven-under 65 giving her a share of the LPGA Founders Cup first-round lead with South Korean Hee Young Park.
Tseng powered to the top of the leaderboard with birdies at the 11th, 13th and 14th holes, followed by an eagle at the par-five 15th and two more birdies at 16 and 17.
Her four-foot birdie attempt at 18 just missed left.
"I tried too hard on the last hole," Tseng admitted. "I think it's harder at the end because you are trying, you're saying, 'Oh, I have three, I have four.' And you want to go five, six, seven, and every hole is harder. You're just trying harder and harder."
Park closed with a bogey on the par-four ninth for her 65, but said she couldn't be disappointed with her day.
"Most of the shots were perfect," she said.
Former world number one Jiyai Shin of South Korea opened with a 66 in the first LPGA event on US soil this season after tournaments in Australia, Thailand and Singapore.
A group on 67 included South Koreans Na Yeon Choi and Hee Kyung Seo along with England's Karen Stupples and Sweden's Pernilla Lindberg.
Tseng, coming off a mammoth 2011 season that included 12 global titles, seven of them on the LPGA tour and two of them at major championships, last month successfully defended her LPGA title in Thailand.
She was even through after 10 holes, with one bogey and one birdie, but came alive on the back nine of the Wildfire Golf Club course.
At the par-five 15th she landed her 219-yard approach shot nine feet from the pin for an eagle.
"It was a little fade, a little cut there," Tseng said. "It was just a little crowd, so I didn't know if my ball was close or not. But I had a good shot, and it was like 9 feet, and a pretty straight putt."
She nabbed her final birdie of the day at the par-three 17th, where she landed her tee shot three feet from the pin.
"I just hit it one shot at a time, because I don't even know what hole I am on," Tseng said. "I just really focus on one shot at a time, try to hit a good drive, get a good second shot and make good putt."
Park, winner of the season-ending Titleholders last year, birdied all four of the par-fives.
"I played really good on the fairway," Park said. "I hit the fairway and then green. Lucky thing was most putts, birdie putts, were uphill. So, that's why I just hit it aggressive."
Shin, who won eight LPGA titles over three years before finishing last season without a victory, played without a bogey and birdied three of her last five holes.
"The weather was perfect this morning, no wind, and the greens were soft," Shin said. "I know this course is pretty tough. Desert course is always tough because the bounce, and the rough is pretty tough. I just more focus to the accuracy with my shot."
Defending champion Karrie Webb of Australia was in a group of 13 players on 68 that included Kraft Nabisco winner Stacy Lewis and US Women's Open champion So Yeon Ryu.