Updated

Women's world No. 1 Yani Tseng posted her second straight four-under 68 on Friday to grab a one-stroke lead after two rounds of the Kraft Nabisco Championship.

She finished 54-holes at eight-under-par 136.

Tseng, the 2010 champion, was the 54-hole leader last year, but Stacy Lewis rallied to win the title. Among Tseng's seven wins in 2011 were the LPGA Championship and Women's British Open, her fourth and fifth major championship victories.

She is off to a flying start this year with three wins in her last four starts and she hasn't finished outside the top eight in five tour events.

Haeji Kang birdied the final hole to shoot four-under 68 and end one back at minus-seven. Sun Young Yoo (69) and Lindsey Wright (71) share third place at six-under-par 138.

World No. 2 Na Yeon Choi carded a five-under 67 to move into a tie for fifth place at five-under 139. She stands alongside Karin Sjodin (67) and Se Ri Pak (69), who would complete the career grand slam with a win this week.

First-round leader Amy Yang struggled to a two-over 74 to slide into a share of eighth place at minus-four.

Tseng started on the back nine Friday and parred her first three holes. After a birdie on the 13th, she made it two in a row with a 12-foot birdie putt at the 14th.

The 23-year-old parred the next three. A birdie on No. 18 put Tseng at seven- under heading to the front nine.

Tseng stumbled to a bogey at the first to dip back to minus-six. She found a greenside bunker with her second shot to the par-five second. However, Tseng got up and down for birdie to recover that lost stroke.

After six consecutive pars, Tseng rolled in a six-foot birdie putt to close out her round.

"I think today was much better than yesterday. This morning I felt more energy coming out today, more than yesterday, and I just feel like today my focus was so much better than yesterday," Tseng said. "I took advantage of every chance out there. Everything else was very good today."

After another solid round of golf, Tseng was going to spend part of her day playing basketball. On Saturday, she'll return to the Dinah Shore Tournament Course at Mission Hills Country Club in search of her sixth major championship victory.

Kang got going with birdies on the second and third to move to five-under. She stumbled to a bogey on the fifth, but recovered that lost stroke with a birdie on No. 7. Kang again traded a bogey for a birdie from the eighth.

The 22-year-old Korean birdied the 11th to move to six-under. She parred the next four holes before converting a birdie effort on the 16th. Kang faltered to a bogey at 17, but came back with a birdie at the last to end one back.

Yang was joined in eighth place by I.K. Kim (70), Eun-Hee Ji (69), Vicky Hurst (70) and Momoko Ueda (69).

NOTES: Lewis, the defending champion, carded a one-under 71 to move into a tie for 42nd at plus-one...The cut line fell at four-over-par 148 with 82 players, including four amateurs, advancing to the weekend...Among those that missed the cut were Women's Australian Open champion Jessica Korda, 2009 champion Brittany Lincicome, 2004 winner Grace Park, Michelle Wie and Sophie Gustafson. Wie missed back-to-back cuts for the first time since she missed three in a row in the 2007 season.