"The pin positions weren't that hard," the 24-year-old Chinese player said.
Defending champion Inbee Park voiced the majority opinion after an opening 74.
"The pin positions were very tough for the first day," Park said. "Half of the pins, we couldn't go at. There were very tough pins out there."
Cristie Kerr agreed after her morning round in the first major of the year.
"The pin on 3 today, it doesn't matter if you hit a pitching wedge, it would be hard to get to, and we're hitting 6- and 7- irons in," said Kerr, tied for sixth after a 69. "The pin on 1 is like 2 yards from the right side of the green. ... Do they have to be that severe? Maybe not, but they're probably compensating for the fact that there's not much rough."
Feng had seven birdies and a bogey.
"This morning, it was playing easier because there was no wind," Feng said.
Feng won the 2012 LPGA Championship to become the tour's first Chinese winner and had two victories late last year. She tied for 16th last week in Carlsbad, her best finish of the season.
"The beginning of this year I was kind of a little lost because I lost a little weight and my swing kind of changed a little," Feng said. "I wasn't swinging very comfortably."
Yin was asked if there was a player she wanted to meet, but was too shy to approach.
"Michelle Wie," Yin said. "If she sat next to me and said 'Hi' to me, I'd probably run."
The 24-year-old Wie laughed when told about Yin's response.
"It's crazy," Wie said. "These girls are starting to make me feel really old."
Wie played a four-hole stretch in 5 under, showing off all the talent that made her a star in her early teens and helped attract players like Yin to golf.
"I just felt comfortable out there," Wie said.
Wie stalled at the end, lipping out a 3-foot par putt on the par-3 17th and settling for par on the par-5 18th.
"I'll take a 67 here," Wie said
Wie birdied the par-5 ninth and par-4 10th, made a 25-foot eagle putt on the par-5 11th and moved into a tie for the lead with a 15-foot birdie putt on the par-4 12th.
She got up-and-down for par from near a steep face in a bunker on the par-4 15th, hitting to 1½ feet with her left foot almost 2 feet above her right.
"Just was aggressive on the holes I needed to be and conservative on the other holes," Wie said
Wie is making her 12th start in the tournament. She was ninth in 2003 at age 13, fourth the following year and tied for third at 16 in 2006.
"I think when you're younger you're kind of fearless," Wie said. "You don't know what failure is."
Wie has two LPGA Tour victories, winning the 2009 Lorena Ochoa Invitational in Mexico and the 2010 Canadian Women's Open. She has been in the top 16 in all five of her starts this year, finishing a season-best fourth in Thailand.
"I'm so grateful to have rounds like these," Wie said.
Paired with 58-year-old Hall of Famer Amy Alcott, Feng rebounded from a bogey on 15 with a birdie on par-4 16th.
"I made a bogey on 15, and she was like, 'OK, let's make two birdies back in the last three holes,'" Feng said. "I was like, 'Yes, ma'am.'"
Alcott shot an 81 in her 36th start in the event she won in 1983, 1988 and 1991. In 1988, she became the first player to take the now-traditional victory leap into Poppie's Pond.
"She was very sweet starting off and we were talkative," Alcott said. "She hits it very solid. Just a very, very talented young player."
The 36-year-old won the last of her five major titles in 2006.
"Just a solid round," Pak said. "The greens got a little firmer, but I got pretty good distance control."
Anna Nordqvist, the winner in Carlsbad for her second victory of the year, opened with a 71. Playing partner Stacy Lewis, the 2011 winner, had a 73.
Lewis struggled off the tee, hitting drives to the right.
"If I can straighten out my driver I'll be right there," Lewis said.