LA JOLLA, California (AFP) — South Korean rookie Shin Ji-yai fired a three-under 69 to take sole possession of first place after the second round of the LPGA Samsung World Championship on Friday.

Shin managed to stay on top of the 20-player field after sharing the first-round lead with compatriot Kim Song-hee on Thursday. She captured her third win of the season last week in Arkansas.

“Today my play was a little bit up and down,” said Shin, who has six victories in 2009.

The 21-year-old Shin rolled in six birdies and three bogeys to reach a total of nine-under 135. Shin is ranked second in the world behind Mexico’s Lorena Ochoa.

Ochoa, a two-time Samsung champion, eagled the 18th hole to shoot 69 and pull to within a stroke of Shin’s lead at eight-under 136 on the Torrey Pines golf course.

Ochoa has won twice this season but not since April when she took the Corona Championship.

Ai Miyazato (68), of Japan, is tied with Ochoa for second place. She made bogey at 18 to fall out of a share of first place.

Sophie Gustafson (70) is alone in fourth place at seven-under 137, while defending champion Paula Creamer (69) is part of a group tied at six-under 138.

Shin holed a 33-foot putt for a birdie at the second hole and then had two straight birdies on Nos. 5 and 6. She made a short putt on number nine for birdie to make the turn at eight under.

At one point she got to 10-under after making a birdie on the 13th hole then scrambled for par on the two closing holes.

“I think No. 17 and 18 were great saves, so I feel good,” said Shin. “I’m a little bit tired. Today was a long day.”

Ochoa sailed a seven-wood over the green at the 498-yard 18th hole but chipped in from 30 feet for an eagle.

“It was for sure a little more of an up-and-down day like a roller coaster,” said Ochoa. “(It’s) funny because at the 18th hole, when I hit my driver in the fairway, I just told Greg, my caddy, ‘I will make this eagle just to make more of an up and down round,’ and we did, so it was kind of a funny way to finish.”