EDMONTON, August 24, 2013 (AFP) - South Korea's Park, who has won three major titles this season, was joined on eight-under 132 by US veteran Cristie Kerr, who carded a 66.
First-round co-leader Angela Stanford carded a 68 that left her tied for third on 133 with France's Karine Icher, who posted a 66.
Lydia Ko, whose victory in this tournament last year at the age of 15 made her the youngest player to win an LPGA title, had shared the overnight lead with Stanford.
The 16-year-old phenom from New Zealand carded a second-round 69 that left her tied for fifth on six-under 134, alongside England's Laura Davies (66) and American Paula Creamer (68).
Park got off to a hot start at the Royal Mayfair Golf Club course with birdies at the first and second. She holed out from a bunker at the par-four first.
"I always love to start with a birdie," Park said. "It's like a good luck charm for me. I almost never finish a round over par when I start with a birdie."
Park, seeking a needed just 25 putts on Friday. Her seven birdies included three in a row at the 14th, 15th and 16th.
"I hit the ball really good, and I obviously putted really good out there," she said. "On these greens, you can two-putt from anywhere. I think it's pretty good. If you slightly over-hit it, you can easily three-putt. So the three-putt is something that I was trying to avoid."
Park played with Kerr in the first two rounds and said they fed off each other's birdies.
"I think it's always good when you're playing with a partner while she's making a lot of birdies and it makes you want to have more birdies," Park said. "It already felt like a final round, and trying to make more birdies and trying to get the momentum going."
Kerr, who had six birdies and two bogeys, agreed.
"It's always fun to play with In-Bee," said Kerr, who is happy with her own game despite a disappointing bogey at 18.
"I'm mad at myself for knocking my last tee shot, but I did so much good stuff in the last couple days," she said.
"I mean, you can't do anything about a porta potty door slamming in your back swing," she added of the noise that distracted her on that tee shot. "I sucked it up, and I made a really good two-putt for bogey."
Ko, who has played in nine other LPGA events this season including four majors, says she's trying to make more decisions, such as club selection, without the help of her caddies.
As an amateur she has hired and played with new caddies every week, often using someone with local experience.
This week Royal Mayfair member Bruce McMillan is carrying her bag.
"The last couple of caddies, local caddies, we've kind of done club selection and stuff together, but this time I decided I wanted to make the decision so Bruce doesn't know what club I'm hitting," Ko said. "I've decided I wanted to be more independent. Doing it this way, it actually helps me to learn to know my clubs better, so I think that's a really good opportunity that way."
Leading second-round scores on Friday in the US LPGA Canadian Women's Open (a-denotes amateur, USA unless noted, par 70):
132 - Park In-Bee (KOR) 67-65, Cristie Kerr 66-66
133 - Karine Icher (FRA) 67-66, Angela Stanford 65-68
134 - Laura Davies (ENG) 68-66, Paula Creamer 66-68, a-Lydia Ko (NZL) 65-69
135 - Kathleen Ekey 71-64, Charley Hull (ENG) 69-66, Park Hee-Young (KOR) 68-67, Stacy Prammanasudh 68-67
136 - Lexi Thompson 71-65, Catriona Matthew (SCO) 70-66, Jessica Korda 70-66, Gerina Piller 70-66, Suzann Pettersen (NOR) 69-67, Caroline Hedwall (SWE) 68-68, Brittany Lincicome 68-68
137 - I.K. Kim (KOR) 71-66, Jodi Ewart Shadoff (ENG) 71-66, Mika Miyazato (JPN) 70-67, Caroline Masson (GER) 70-67, Brittany Lang 70-67, Christel Boeljon (NED) 65-72
138 - Danielle Kang 71-67, Ai Miyazato (JPN) 70-68, Thidapa Suwannapura (THA) 70-68, Pornanong Phatlum (THA) 69-69, Choi Na-Yeon (KOR) 67-71