World number one Lydia Ko missed the cut for only the second time in her career as veteran Cristie Kerr opened a one-shot lead at the Kia Classic on Friday.
New Zealand's Ko, 19, fired a level-par 72 at the Aviara Golf Club in Carlsbad, California, but it was not enough to advance her to the weekend following her two-over-par opening round 74 on Thursday.
With the cut coming at one-over, Ko missed out on a place in the third round by just one stroke -- ultimately paying the price for two bogeys in her final three holes on Friday, including a three-putt on the 18th.
"I was in an okay position after halfway then I had a really bad finish, missed two short putts at 16, 17 and obviously 3-putting the last," Ko said.
"I can't do anything about it. I tried my best out there to hopefully put myself in better position going forward, but I can't do anything about it."
Ko said she planned to use the extra time to head to Palm Springs to get in some extra practice ahead of the ANA Inspiration, the first major of the season.
Kerr held a share of the first round lead with Mo Martin and South Korea's Chun In-Gee, but she pulled away from the pack.
She started on the back nine and led by as many as three strokes before faltering coming in.
"I think it's a course that demands a lot of you," Kerr said. "When you hit a bad shot you have to be able to recover and really stay focused the whole day.
"It was a very long day. I feel like my focus left me a little bit at the end, but I played really well," added Kerr, an 18-time winner on tour who won this event in 2015 for her first of two victories that season.
Kerr made two bogeys in her last four holes as her lead dwindled to one.
Her three-under 69 put her at nine-under 135, one stroke in front of Martin, who carded a 70, and South Korea's Lee Mi-Rim, who shot her second straight 68 for 136.
It was a further two strokes back to South Korea's Hur Mi-Jung, France's Karine Icher and Americans Austin Ernst and Jackie Stoelting on 138.