DALLAS, May 2, 2014 (AFP) - Pettersen played without a bogey and her five-under par 66 gave her a one-stroke lead over a group of six players headed by American star Michelle Wie.
Pettersen is playing her second event since she was sidelined for four weeks with a back injury and admitted she's still finding her groove.
"I feel good," she said. "I've got to kind of pace myself a little bit. I can't do too much early in the week. So I have a lot of spare time to fool around with."
Pettersen moved atop the leaderboard with birdies at seven and eight, her 16th and 17th holes of the day at Las Colinas Country Club in suburban Dallas.
She said she wasn't sure what to expect when her painful back forced her off the course, having missed about eight months with a back problem a decade ago.
Encouragingly, her game seems to be in good shape after her layoff.
"I'm hitting the ball great," said Pettersen who finished tied for 28th last week in San Francisco. "Today I was actually feeling a little bit tense to start, which is a good sign. So nice to be back."
Wie who clinched her third LPGA victory two weeks ago in Hawaii, had four birdies, two bogeys and an eagle in her four-under 67.
She shared second place with Cristie Kerr, Christina Kim, Germany's Caroline Masson and rising talents Cydney Clanton and Dori Carter.
"It was a fun day out there today," said Wie, whose round included an eagle at the par-five 10th. "Good crowd. A little bit cold in the morning, but I'm happy with my round. I started off hot, and then I had a little three putt, just couldn't get anything going after that, but you know, the eagle is always nice."
Defending champion and world number one Park In-Bee of South Korea and world number three Stacy Lewis both opened with rounds of even-par 71 to lie tied for 35th.
Park's card was marred by a double-bogey six at the par-four 15th. She also had two bogeys and four birdies.
"I hit it into the water once today, and I hit it out of bounds once today," Park said. "It was just one of those kind of days. Nothing went really wrong, but just a couple of bad shots that really penalized me today.
"But I still have three more days, and I think there is still a lot of birdies out there," she said.
Leading first-round scores on Thursday in the $1.3 million LPGA North Texas Shootout (USA unless noted, par-71):
66 - Suzann Pettersen (NOR)
67 - Dori Carter, Cydney Clanton, Cristie Kerr, Christina Kim, Caroline Masson (GER), Michelle Wie
68 - P.K. Kongkraphan, Amelia Lewis, Lin Xiyu (CHN)
69 - Chella Choi (KOR), Jodi Ewart Shadoff (ENG), Juli Inkster, Lorie Kane (CAN), Kang Hae-Ji (KOR), Katherine Kirk (AUS), Lee Mi-Hyang (KOR), Jenny Shin (KOR)
70 - Moira Dunn, Paz Echeverria (CHI), Victoria Elizabeth, Natalie Gulbis, Felicity Johnson (ENG), Danielle Kang, Brittany Lang, Meena Lee (KOR), Megan McChrystal, Azahara Munoz (ESP), Haru Nomura (JPN), Ryann O'Toole, Pornanong Phatlum (THA), Reilley Rankin, Thidapa Suwannapura (THA), Lexi Thompson, Yoo Sun-Young (KOR)