The 28-year-old Wahlin, whose career was disrupted in 2009 when she was diagnosed with skin cancer, made a 26-foot birdie putt on the 18th for the lead to go along with six other birdies and one bogey.
The Swede is two shots ahead of four other golfers and four shots ahead of Lexi Thompson (70), the 16-year-old American who is the youngest winner on the LPGA Tour.
Thompson recovered from a slow start to make three birdies on her final three holes. The teenager came into the tournament as one of the favorites, having won the Navistar LPGA Classic in September.
“I struggled with my putter until the 16th hole,” Thompson said. “Then I figured some things out so it went well for the last three. I hit it well, just putts didn’t drop.”
Michelle Wie, looking for her first win of the year, was seven shots back after shooting 73. She’s tied for 54th in the 108-player field.
Wie, who was hampered last year with a back injury, is 17th in the rankings. She missed several birdie chances, including on the ninth – her final hole of the day.
“Frustrating,” Wie said. “It was one of those days where nothing went in and nothing went my way. It was pretty frustrating that I was 1 over par. I have tomorrow and my game is feeling pretty good. So I just have to go out there and score.”
Wahlin was diagnosed with skin cancer in 2009 while in Dubai. She played only a few events on the European Ladies Tour last year and several on the Swedish tour.
The two-time European Ladies Tour winner has fully recovered from the cancer. She wears sun screen and protective clothing that covers her arms while avoiding tournaments in sunnier locales such as Australia and Portugal. While Dubai normally can reach 122 degrees in the summer, temperatures in December are much cooler.
“I just have to be careful. I mean I have that kind of skin which is quite sensitive to the sun,” Wahlin said. “I thought is it really worth it to be out on the golf course in the sunny countries or is it better that I just quit playing golf and do something else. But I still have to live my life and golf is my life, or a big part of my life.”
Wahlin has struggled since returning to the tour full time this year, failing to earn a top-10 finish this season. She finished 52nd at last week’s Indian Open but said her cancer has given her a fresh perspective.
“Golf is not so important anymore,” Wahlin said. “If I have a bad round, I’m still disappointed. But it’s not the end of the world like it used to be. So that is a good thing.”
Brewerton had six birdies and a bogey. It was a marked improvement from the Indian Open, where the Welsh golfer finished 74th.