LOS ANGELES (AP) -- Jin Young Ko had five back-nine birdies in a 7-under 64 at demanding Wilshire Country Club for a share of the second-round lead Friday with Nasa Hataoka in the DIO Implant LA Open.
Five strokes behind first-round leader Alison Lee after a 71, the top-ranked Ko moved into position for her second victory of the season in the first of two straight LPGA Tour events in the Los Angeles area.
"My putting was so good today," Ko said. "I wasn't expecting to play really well today because in the afternoon it's always hard to play this course. But my putting was good, so I'm happy with it."
Hataoka birdied her final three holes for a 68 to match Ko at 7 under. Eighteen players were unable to finish the round because of darkness.
After dropping a stroke on the par-4 ninth, Ko birdied Nos. 11-14 and added her eighth birdie of the day on the par-4 17th.
"I didn't think I played 5 under on the back nine," Ko said. "I didn't know that. I was in the zone."
The 26-year-old South Korean star won in Singapore early last month for her 13th LPGA Tour title. She won five times last year.
"I have two more rounds and nobody knows how it goes," Ko said. "So working hard and focus on it and go get it"
Hataoka had seven birdies and four bogeys. The 23-year-old from Japan has five LPGA Tour victories, winning twice last season.
"The wind was pretty strong," Hayaoka said. "The greens are pretty tight, narrow. So my plan was to hit the green, not try to be too aggressive. On the back nine, the wind kind of got weaker, so I was able to hit at the pin."
Hannah Green was third at 5 under after a bogey-free 67. The Australian won her two LPGA Tour titles in 2019.
"I'm very pleased," Green said. "I guess today's round kind of felt like even more under par than what it was. I was pretty solid with my putting all day today which was nice because yesterday I had a couple three-putts."
Fellow Australian Minjee Lee, the 2019 winner, had a 68 to match Haeji Kang (69) at 4 under. Inbee Park (67) topped the group at 3 under.
"You've got to really be careful how you play the holes -- and you can't get too greedy," Park said. "Even though the course is short, it's just really tough."
Lee was 2 under, following her opening 66 with a 74.
Defending champion Brooke Henderson, playing alongside Ko, shot 76-72 to miss the cut.
The Palos Verdes Championship is next week.