Second on the LPGA Tour in birdies, Choi had four of them without a bogey. The first-round leader by a stroke, she is motivated by missing a cut for the first time as a pro last week at the LPGA Championship.
Fellow South Korean Inbee Park shot a 66, Christina Kim had a 67 and Alena Sharp a 68 to share second place at 9-under 133.
Angry at herself after missing the cut last week, Choi discarded her putter and got a new one. As a result, she's needed just 53 putts in 36 holes while getting to 11-under 131. She doubled her first-round lead.
``I had confidence out there with my friend Inbee Park,'' she said. ``We enjoyed it. No bogeys today, so I feel perfect.''
They'll also play together for the third straight day in the final pairing on Saturday.
Park three-putted for a bogey at the 16th hole, then turned around and holed a 20-yard bunker shot for eagle at the 17th.
``I was a little disappointed (with the bogey) but that eagle just washed that away,'' she said. ``It gave me a lot of confidence going into the weekend that I'm that much closer to the leader.''
Sharp has never finished better than seventh in her 4 1/2 years on tour. As a result, she's not used to seeing her name on the leaderboard.
``I was a little nervous today,'' the Canadian said. ``I just wanted to get out and get started. Then I got into the way I felt yesterday - just really relaxed. I'm happy with the way my game is going into the weekend. I like my position.''
Kristy McPherson holed a 60-degree wedge from 75 yards on the 18th hole for an eagle and a 68 to lead a pack of six players at 136.
``It's always nice when you don't have to putt on the last hole,'' she said.
Joining her at 136 were Song-Hee Kim (66), In-Kyung Kim (66), Beatriz Recari (67), Stacy Prammanasudh (67) and Stacy Lewis (69). Lewis, who was born in Toledo, was supported by a large number of fans and relatives wearing ``Lew Crew'' T-shirts.
Defending champ Eunjung Yi had a 68 and was eight shots back.
For Creamer, winner of the Farr two years ago, missing the cut means a weekend away from the pain associated with playing with her surgically repaired left thumb.
``I'm very disappointed in how I played but it's two more rounds under my belt,'' she said. ``I'm getting used to getting out there and there's some things I need to work on. It's just the hard part is being able to work on them.''
Still recovering after having the ligament damage repaired in her thumb, Creamer has played in the last three tournaments.
``Probably three in a row is too much coming out at first,'' she said. ``But I feel like I have an obligation. I love coming to this golf course and the fans ... you don't want to miss that.''
Creamer, who's No. 1 backer is the tournament sponsor, was going to stay in Toledo to practice for the U.S. Women's Open at Oakmont. She was trying to forget her injury.
``I'm trying not to dwell on my thumb as much,'' she said. ``I do have some thumb problems but you just have to work through them.''
